State officials who run US elections braced for possible intervention by President Donald Trump's administration in Tuesday's midterms, fearing federal authorities loyal to the president could disrupt voting, challenge ballot counts or try to block the certification of unfavorable results.

Cover image: US President Donald Trump, pictured making baseless claims of election fraud ahead of the 2021 US Capitol riot, has declined to rule out extraordinary measures around the 2026 midterm vote © Brendan Smialowski / AFP/File Trump has repeatedly questioned the integrity of US elections – notably his 2020 loss to former president Joe Biden – and has urged his party to "nationalize" voting in at least 15 places.

The Constitution gives the US states the primary authority to organise and administer elections, and the president has no direct role in running elections.

US courts have so far rebuffed most of the Trump administration's legal challenges that have attempted to influence voting procedures or who is eligible to cast a ballot. The White House says it is protecting election security. With voting in the midterms under way, here are some of the potential flashpoints.

Who gets to vote The Justice Department (DOJ) has requested voter registration data from all 50 states. While many states complied with the request, the DOJ sued another 30 states and the District of Columbia to obtain their voter registration lists saying it needs them to find non-citizens. It subsequently lost more than two dozen of those cases in the courts.

The DOJ demanded that ballots be set aside from about 20,000 people in California and more than 400 in Washington state whom it suspects are non-citizens. The US Supreme Court rejected the request handing the Trump administration a major reversal on the eve of the midterms. Washington state has also refused the demand.

Studies have repeatedly found non-citizen voting to be exceptionally rare. Doing so risks stiff fines, imprisonment or deportation.

“The Heritage Foundation’s database of documented cases of voter fraud includes 100 cases of noncitizens voting from 1982 to 2025. That is about 0.000008 percent of more than 1.3 billion votes cast in presidential elections during that time,” the New York Times reported in April.

The Justice Department has warned election officials in every state that they themselves could face prosecution if they knowingly allow non-citizens to vote.

Trump has also offered $1 million for information leading to a voter fraud conviction, without offering details.

At polling stations The Justice Department announced plans to send around 1,000 election monitors to all 50 states – its largest deployment ever.

At the same time, the Trump administration broke with two decades of precedent by not inviting elections observers from the Organization for Security and Co-operation in Europe (OSCE) to monitor the midterms. The decision drew widespread criticism from election integrity experts, human rights groups and Democratic lawmakers.

Democrats criticized the Trump administration for aligning with autocratic regimes like Russia and Belarus, the only other OSCE members to reject independent observers.

Election monitoring is a decades-old practice, but Democrats and voting rights groups fear monitors from Trump's DOJ could intimidate voters.

The Justice Department says they will be unarmed, barred from interfering with voting, and drawn from neither the FBI nor Immigration and Customs Enforcement (ICE).

The administration says it is not planning operations targeting voting centers, although Homeland Security Secretary Markwayne Mullin has said ICE agents could serve warrants there.

When questioned, Trump has declined to rule out declaring a national emergency or invoking the Insurrection Act, which allows the president to deploy troops at home.

A Civil War-era law bars troops and armed federal agents from polling places, and legal experts say an emergency declaration would not give the president power over elections.

US Democrats have expressed concern that polling station monitoring by federal officials could amount to intimidation © Austin Johnson / AFP Counting the votes Federal agents could seek warrants or subpoenas for ballots, voting machines or records – potentially disrupting the count.

In January, the FBI seized ballots and other 2020 election records in Fulton County, Georgia, a focus of Trump's false claims that he won that year.

State election officials warn that similar action during an active count could undermine safeguards tracking how ballots are handled.

Trump could allege fraud involving mail-in ballots, voting machines or votes counted after election night, fueling demands for recounts or attempts to halt counting.

But the US Supreme Court ruled in June that states may count mail ballots postmarked by election day that arrive afterward, and courts can intervene against unlawful disruption.

After election day The Justice Department has already sued Alaska to delay certification of its Senate race if Republican incumbent Dan Sullivan narrowly loses to Democrat Mary Peltola, citing a second candidate named Dan Sullivan who it says is trying to confuse voters, which he denies. Trump said he ordered the lawsuit.

Experts say federal law does not allow the department to block certification, which courts can compel officials to carry out.

Trump could pressure state officials to dispute results, as he did after losing the 2020 election. Experts warn unresolved disputes could also delay the seating of newly elected lawmakers in January.

But courts have repeatedly upheld states' authority over elections, and Democrats and voting rights groups have assembled legal teams to fight any potential interference.

Democratic party leaders, lawmakers and others spent weeks gaming out more than 150 scenarios of possible federal interference in a "war room" ahead of the midterms, focusing on countering administration moves in the days after the vote.

Citizens for Responsibility and Ethics in Washington working alongside a coalition of voting rights groups like the ACLU and Democracy Forward, has tried to prepare legal roadblocks to battle any federal election interference.