But some of the biggest delays at voting booths were also in Georgia.
Goodstein, however, still believes that Trump "is uniquely disfavored" and numerous voters who strongly disapprove of Trump will take to the polls, allowing the Democrats to regain the House of Representatives.
AP VoteCast also shows a majority of voters considered Trump a factor in their votes.
A majority of the 113,000 voters surveyed said the country is headed in the wrong direction.
An epic battle for control of Congress and the future of Donald Trump's presidency was wrapping up Monday as both parties made their final appeals to voters.
He amplified that message with an advertisement linking Democrats and immigrants to violent crime, which aired on NBC on Sunday night.
The president's current job approval, set at 40 percent by Gallup, was the lowest at this point of any first-term president in the modern era. But they failed to win the governor's mansions in OH and Florida, two big states where they'd had hopes for marquee victories.
All 435 seats in the House of Representatives, 35 seats in the 100-member Senate and 36 governorships were up for grabs. Elizabeth Warren in MA, according to CNN projections. Kirsten Gillibrand of New York and New York Gov. Andrew Cuomo.
Former vice president Joe Biden, often touted as a possible Democratic candidate to take on Trump in 2020, said he'd be "dumbfounded" not to win the House.
Trump was watching the results roll in from the White House, where he spent the day holed up with friends and family. Among those expected: Vice President Mike Pence and former House Speaker Newt Gingrich, an informal adviser to the president.
In the last 24 years, Democrats have only controlled the House of Representatives for four years.
The political and practical stakes were sky-high.
Other media outlets also projected that the Democrats would pick up at least the 23 Republican-held seats they needed to win to gain a majority. A similar 88 percent of those who approved of Trump voted for the Republican House candidate.
Some Democrats have already vowed to force the release of his tax returns. Without another Democratic victory, it seems, Democrats will remain the minority in the Senate.
Daniel McAdams, executive director at the Ron Paul Institute, agrees, noting that the Democrats "ran a frightful campaign" under the slogan "Trump is racist, vote for me". Nevada could be more important, because Dean Heller is the most vulnerable Senate GOP incumbent in the nation, and Democrats probably need to win his seat to seize the majority. She urged voters to "vote against radicalism, bigotry, and corruption" and "for fantastic candidates all over the country - including a historic number of women".
But after almost two years of increasingly heated and polarised politics in the US, Democrats sought to turn anger into votes.
The demographic divides were coloring the political landscape in different ways.
If Democrats capture the House, they could block Mr Trump's policy agenda and launch congressional investigations into Trump's administration, including his tax returns, possible business conflicts of interest and the nature of his 2016 campaign's ties to Russian Federation.
Democrats faced a far more hard challenge in the Senate, where they were nearly exclusively on defense in rural states where Trump remains popular.
The two parties were also tangling in several crucial governors' races, including in Midwest battleground states such as Wisconsin, Ohio, Iowa and MI. And only twice in the past eight decades has the president's party picked up House seats in the midterms. McAdams believes that Democrats failed to offer an "alternative narrative" and that might hurt them at the ballot box.