Democratic candidates are forecast to receive more than 60.5 million votes in total for the house once the final ballots have been counted.
If accurate, the figure would be the closest an opposition party has come in a midterm election to matching the president’s backing two years earlier.
Donald Trump received just shy of 63 million votes in 2016, as he lost the popular vote but achieved a comfortable victory under the electoral college system.
House Democrats are currently on course to hit around 96 per cent of Mr Trump’s vote share from two years prior, beating the record 92 per cent of Richard Nixon’s share from 1968 seen in the subsequent midterms.
Pollster Nate Silver described the number of voters mobilised for the Democrats during the midterms as “crazy”, given turnout is usually considerably lower than in presidential elections.
He tweeted: “Of course, this reflects 3 things we already knew: 1) Trump was elected despite losing the popular vote; 2) D’s won by a big margin this year and 3) Turnout was VERY high.
“But Trump is a very unpopular president, and I don’t think that’s totally sunk in yet in how he’s covered.
“About 60 million people turned out to vote for Democrats for the House this year. That is a **crazy** number. (Republicans got 45m votes in the 2010 wave.)
“And this was sort of missed. Why so many stories about Trump voters in truck stops and not so many about ‘the resistance’?”
The 6 November election saw Republicans lose control of the House of Representatives, congress’s lower chamber, to the Democrats. However, the GOP was able to make gains in the Senate.
Polarisation of views on Mr Trump’s performance during his first two years in office, coupled with divisive debates in the lead-up to polling day on immigration, healthcare and taxes are thought to have spurred the highest turnout percentage in a midterm since 1914.
At least 49.2 per cent of eligible voters took part in the election, the United States Elections Project estimates — a marked contrast to the last midterms in 2014, when just 36.4 per cent of voters cast their ballot, the lowest turnout since the end of the Second World War.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies