The first national elections since Trump captured the White House in a stunning 2016 upset will be a referendum on the polarizing Republican president and his hardline policies, and a test of whether Democrats can turn the energy of the liberal anti-Trump resistance into victories at the ballot box.
Striking a dark tone at a rally in Indiana on Monday evening, Trump accused Democrats of “openly encouraging millions of illegal aliens to break our laws, violate our borders and overrun our country."
All 435 seats in the US House of Representatives, 35 US Senate seats and 36 governorships are up for grabs in elections focused on dozens of competitive races from coast to coast that opinion polls show could go either way.
Democrats are favoured by election forecasters to pick up the minimum of 23 House seats they need for a majority, which would enable them to stymie Trump’s legislative agenda and investigate his administration.
Republicans are expected to retain their slight majority in the US Senate, currently at two seats, which would let them retain the power to approve US Supreme Court and other judicial nominations on straight party-line votes.
If they do win control of the House, Democrats will try to harden US policy toward Saudi Arabia, Russia and North Korea, while maintaining the status quo on hot-button areas like China and Iran.
US stocks opened flat on Tuesday as investors awaited the election results. Political gridlock between the White House and Congress could hinder Trump’s pro-business agenda and raise concerns about US political instability, but investors may have already priced this in.
Analysts expect pressure on stocks if Democrats gain control of the House and a sharper downward reaction if they take the Senate too. If Republicans hold their ground, stocks could gain further, with hopes of more tax cuts ahead.
In a last-minute controversy, NBC, Fox News and Facebook on Monday pulled an ad by Trump’s campaign that critics have labelled racist. The 30-second spot featured courtroom video of an illegal immigrant from Mexico convicted in the 2014 killings of two police officers, juxtaposed with scenes of migrants headed through Mexico.
Critics, including members of Trump’s own party, have condemned the commercial as racially divisive. CNN had already refused to run the ad, saying it was “racist."
Facebook also blocked about 115 user accounts after US authorities tipped it off to suspicious behaviour that may be linked to a foreign entity, the company said hours voting began.
US intelligence agencies have concluded the Russian government meddled in the 2016 election with social media posts meant to spread misinformation and sow discord, an accusation denied by Moscow.
Voter turnout could be the highest for a midterm election in 50 years, experts predicted. About 40 million early votes were likely cast, said Michael McDonald, a professor at the University of Florida who tracks the figures. In the last such congressional elections in 2014, there were 27.5 million early votes.
At least 64 House races remain competitive, according to a Reuters analysis of the three top nonpartisan forecasters, and Senate control was expected to come down to a half dozen close contests in Arizona, Nevada, Missouri, North Dakota, Indiana and Florida.
Democrats could also recapture governor’s offices in several battleground states such as Michigan, Wisconsin and Ohio, a potential help for the party in those states in the 2020 presidential race.
Wrapping up the campaign in recent days, Trump repeatedly raised fears about immigrants, issuing harsh warnings about a caravan of Central American migrants that is moving slowly through Mexico toward the US border.
A debate about whether Trump’s rhetoric encouraged extremists erupted in the campaign’s final weeks after pipe bombs were mailed to his top political rivals allegedly by a Trump supporter who was arrested and charged, and 11 people were killed in a shooting at a Pittsburgh synagogue.
Trump said in an interview with Sinclair Broadcasting on Monday that he wished he had a softer tone during his first two years in office - even as he continued his relentless attacks on political rivals.
Trump blamed the political vitriol on election season.
“I’d love to get along and I think after the election a lot of things can happen," Trump said. “But right now they’re in their mode and we’re in our mode."
White House spokeswoman Sarah Sanders said Trump planned to spend Election Day making phone calls and monitoring the races from the White House, and would watch the results later with family and friends. He had already voted by absentee ballot.
Many Democratic candidates in tight races shied away from harsh criticism of Trump, focusing instead on bread-and-butter issues like maintaining health insurance protections for people with pre-existing medical conditions and safeguarding the Social Security retirement and Medicare healthcare programs for senior citizens.
But Democratic former President Barack Obama hit the campaign trail in the election’s final days to challenge Trump, questioning his policies and character.
“How we conduct ourselves in public life is on the ballot," Obama told Democratic volunteers in suburban Virginia.