US Midterm Elections 2026:
Political and Security Outlook

On 3 November, approximately 250 million US citizens will be eligible to vote in the country’s midterm elections, which will determine the composition of both chambers of Congress, the Senate and the House of Representatives or “House”. Voters will elect all 435 members of the House, 35 of the Senate’s 100 seats (33 regular contests plus special elections in Ohio and Florida), 39 state and territorial governors, and 33 attorneys general, as well as numerous state and local officials.

Members of the House of Representatives serve two-year terms and are elected by direct popular vote in single-member congressional districts. Each state is allocated seats proportionate to its population. Senators serve six-year terms and are elected by direct popular vote in a single statewide constituency, with two per state regardless of population.

The United States has a de facto two-party political system. Apart from two independent senators and one independent member of the House, every seat in Congress is held by either the Republican or the Democratic Party. The Republican Party currently holds narrow majorities in both chambers: 53 of 100 seats in the Senate, and 218 of 435 in the House, where two seats are vacant. The midterm elections could therefore result in a change of control in either or both chambers of Congress.

Midterm elections are widely treated as a barometer of public support for the sitting president and governing party. Historically, the president’s party has lost seats in the House in almost every midterm election, although this pattern is less consistent in the Senate.

As of 27 October, President Donald Trump has an approval rating as low as 31 per cent according to some polls, the lowest figure recorded across both of his presidential terms. In the November 2025 off-year elections, Democrats gained the Virginia governorship, retained control in New Jersey and secured victories in several other state-level races.

Recent polling and election forecasts indicate that the Democratic Party is well positioned to regain control of the House, with many projecting a net gain of 10–20 seats, significantly above the three seats required to secure a majority. In the Senate, polls suggest a narrower result, with the Democratic Party’s chances of winning a majority depending on key races in Texas, Ohio, Michigan, and Iowa.

Unlike proportional representation systems, where seats are allocated according to parties’ share of the vote, House elections are contested in individual congressional districts, while Senate elections are decided at the state level. Consequently, nationwide polling figures do not necessarily translate into a proportional distribution of congressional seats. Most House and Senate seats are typically considered “safe”; the party that holds them is likely to retain control. “Swing seats”, which could flip from one party to the other, constitute the minority. Ahead of the 3 November midterms, election forecasters have identified between seven and 14 competitive races in the Senate and 40-46 in the House.

The relatively small number of competitive seats reflects established voting patterns, the geographic distribution of party support and gerrymandering, the deliberate redrawing of congressional district boundaries to favour one political party over another. As a result, a relatively small number of competitive swing seats will be critical in determining which party controls Congress.

US elections typically hinge on domestic policy issues. However, the 2026 midterms will take place amid several international crises, with global policy issues occupying a central position in campaigns. A Pew Research Center poll from October indicates that a majority of both Republican and Democratic registered voters see foreign policy as a “very important” issue, ranking it ahead of topics such as violent crime.

The vote will occur at a time of growing tensions between the US and Iran. The conflict has contributed to rising prices for fuel and essential goods in the US and worldwide. According to a Pew Research poll from early October, 65 per cent of Americans disapproved of the White House’s handling of the conflict. While most Republicans are in favour of the conflict, the study found that “Republicans and Republican-leaning independents have grown more negative about [it]”.

Voters also link the Iran war with the economy and the increased cost of living. In May, a poll by the Institute of Global Affairs at Eurasia Group found that almost 80 per cent of US adults thought that the Iran war had affected the cost of living to some extent (with 45 per cent assessing that the war had affected it “a great deal”). With fuel prices and the cost of other essential goods rising in the second half of 2026, the economic impact of the conflict will likely undermine Republican electoral prospects.

In the past two years, the US has also become more directly involved in influencing the politics of Latin America. This strategy has included the controversial capture of Venezuelan President Nicolás Maduro and the imposition of a fuel blockade on Cuba that has pushed the government to the brink of collapse. While less prominent overall than the Iran war, assessments of US policy in LATAM are likely to be major political factors in US states that have large Latin American (particularly Cuban and Venezuelan) diaspora communities, such as Florida, Texas, New York, and California.

US relations with Israel are almost certainly the most divisive foreign policy issue shaping the vote, particularly within the Democratic Party. Since the 7 October 2023 Hamas attack and the subsequent war in the Gaza Strip, repeated waves of protests have taken place in the US. In early 2026, a Gallup poll found that, for the first time, Americans were no longer more sympathetic towards Israelis than Palestinians, reflecting declining sympathy for Israel among Democrats and younger Americans, particularly those aged 18–34.

Within the Democratic Party, growing criticism of Israel has almost certainly contributed to the victory of several Israel-sceptic candidates at the pre-midterm primaries. These include seven House candidates and the party’s Senate nominee in Florida, all aligned with the Democratic Socialists of America (DSA), a grassroots democratic socialist organisation that operates independently of the Democratic Party but endorses candidates competing in its primaries. With DSA candidates mostly running in “safe” Democratic seats, the upcoming midterms will highly likely result in a larger Israel-critical contingent entering Congress.

Despite the prominence of international issues in the election campaign, the midterms are unlikely to fundamentally alter US foreign policy, given the president’s extensive executive powers over foreign affairs. Even if Democrats gain control of Congress, their ability to constrain the White House’s actions abroad will remain limited. Congress has substantial constitutional powers over federal spending, military authorisations and arms transfers. However, the president can veto legislation, requiring a two-thirds majority in both chambers to override. This makes it difficult for a narrowly divided Congress to impose restrictions opposed by the White House. Instead, Democrats would likely use congressional oversight and budgetary powers to pressure the administration into policy concessions over the medium to long term, while strengthening their position ahead of the 2028 presidential election.

The US midterms occur at a time of high polarisation in the US. Over the last decade, US elections have been affected by notable levels of unrest and occasional political violence. A case of US election-linked violence was the 6 January 2021 storming of the Capitol building by supporters of President Trump. Between 2016 and 2025, there were reported incidents of voter intimidation near polling stations, as well as separate plots and attempts to kidnap or assassinate political figures. The 2024 presidential campaign saw several high-profile incidents of political violence, including two assassination attempts against Republican candidate Donald Trump, linked arson attacks targeting ballot drop boxes in Washington and Oregon, and a separate arson incident in Arizona.

The current midterm electoral campaign has also been the subject of disinformation campaigns, including operations linked to foreign state actors. Researchers have identified a new phase of “Operation Matryoshka”, a Russian-linked disinformation campaign active since at least 2023. The operation has increasingly targeted US politics, using AI-generated videos and fabricated news reports to discredit Democratic candidates. Separately, in October, the social media platform X announced the suspension of more than 13,000 accounts suspected of involvement in foreign influence operations linked to Russia, Iran and China.

Additional research has identified numerous false narratives circulating across social media and other online platforms ahead of the midterms, including allegations of electoral fraud, candidate misconduct and misleading claims about political policies. There has also been an increase in so-called “pink slime” websites, which present partisan political content as independent news reporting or impartial information.

High levels of political polarisation, the spread of disinformation and previous incidents of election-related violence are likely to increase the risk of civil unrest surrounding the vote. The midterms are taking place against a backdrop of sustained protest activity across the US in recent years. This has included large nationwide demonstrations, notably the “No Kings” protests, which have attracted millions of participants; widespread protests against Immigration and Customs Enforcement (ICE) operations; demonstrations against the war in Gaza, particularly across university campuses; and numerous smaller, localised protest movements.

There are several potential flashpoints for protests during the election. US federal law bars armed federal agents or troops from being present at polling stations, and, in February, a Department of Homeland Security (DHS) official told state election officials that ICE would not be deployed during the vote. However, President Trump has declined to rule out deploying ICE or the National Guard, stating that he would do “anything necessary” to guarantee fair elections, and has called on Republicans to “nationalise the voting”. Any visible deployment of federal agents or troops near polling stations or vote-counting centres has the potential to trigger protests, particularly in cities such as Los Angeles and Minneapolis that have experienced large-scale immigration enforcement operations, and could lead to confrontations between demonstrators, federal personnel and counter-protesters.

Campaign events represent a further potential flashpoint ahead of the vote. President Trump is undertaking a month-long rally tour in support of Republican candidates, with several events already disrupted by protesters. Further demonstrations and disruptions are likely in the final days of campaigning, particularly in states with competitive races, while confrontations between protesters, counter-protesters and security personnel remain possible.

The risk of unrest will likely peak after polls close rather than on election day itself. With control of the Senate expected to hinge on a handful of close races, and with some states counting ballots for days after the vote, final results in some of the key races may not be disclosed for several days. In multiple states, including California, New York, Nevada and Washington, postal ballots can be counted if received after election day, provided they meet the relevant postmark requirements.

Previous elections have demonstrated how prolonged vote counts result in protests being staged outside counting centres. In 2020, demonstrators gathered at Detroit’s main absentee ballot counting centre demanding officials “stop the count”, while armed protesters assembled outside an election centre in Phoenix, Arizona. Closely contested results, particularly if accompanied by allegations of electoral fraud, would likely trigger protests outside of locations associated with vote counting and election administration.

Washington, D.C., is likely to be a focal point for national-level demonstrations following the vote, particularly if the results are disputed. The city has maintained a National Guard deployment since August 2025, which the administration has extended until January 2029, with the continued presence of armed troops in public spaces likely to increase tensions during demonstrations.

Most large-scale protests in the US remain peaceful, although they can cause traffic disruption and other localised impacts. However, heightened political tensions, disinformation and other developments could contribute to an escalation in unrest, increasing the risk of isolated violence and confrontations between demonstrators, counter-protesters and security forces.

In a September 2026 study, the Centre for Strategic and International Studies (CSIS) noted that “[t]errorists have attacked or plotted against candidates, the people who run and certify the vote, or the crowds an election draws in each of the past several election cycles in the United States.” However, CSIS data suggest that such incidents have become more frequent in recent years, with ten of the 11 recorded cases taking place since 2021. Only one incident was specifically planned for election day, while none is confirmed to have targeted a polling station. Most incidents targeted political candidates during campaigns or election officials involved in certifying results, likely indicating that the threat is likely to persist throughout the electoral cycle, including during the post-election counting and certification period.

The campaign has already been subject to possible targeted violence and intimidation. On 6 September 2026, a man was arrested after a reported attempted assault targeting the Democratic candidate for Ohio governor during a campaign stop, injuring several people before being stopped by state troopers. In October, the FBI opened an investigation into a wave of suspicious letters, some containing an unidentified powder, sent to election offices in at least 32 states and to congressional offices, forcing evacuations only weeks before the vote.

Incidents during previous electoral cycles and broader terrorism trends in the US suggest that the primary threat will come from “lone actors”, individuals who become radicalised independently and operate without direct involvement in organised terrorist groups. Individuals motivated by far-right or far-left extremism are among the most likely to conduct election-related attacks, potentially targeting political candidates, supporters or events, or attempting to disrupt voting proceedings.

Unlike the UK, the US does not maintain a publicly available, tiered national terrorism threat level. Instead, the Department of Homeland Security (DHS) issues periodic advisories and alerts through its National Terrorism Advisory System (NTAS) in response to specific threats or changes in the security environment. No terrorism advisory has been issued specifically for the midterms, although the FBI has separately warned of potential threats and intimidation targeting election workers and polling locations, without identifying a specific terrorist threat.

The 3 November US midterms will likely be characterised by heightened political tensions across the US, with a higher risk of protests, isolated violent incidents, and localised disruptions in the days surrounding the vote. While most demonstrations are likely to remain peaceful, contested results and delays in vote counting could trigger further mobilisation, particularly near election offices, government buildings and other politically significant locations. Travellers to the US are unlikely to face significant disruptions outside areas directly affected by election-related events. However, protests could cause localised disruption, particularly in Washington, D.C., and major cities in states with closely contested races. There is also a risk of isolated incidents of political violence or terrorism, particularly around campaign events and electoral facilities.

Travellers are advised to monitor local developments, avoid political gatherings and large-scale demonstrations, and allow additional time for journeys through affected areas.