Voters in Massachusetts settled two key races early on election night as Democratic Sen. Ed Markey waltzed to re-election and the state was quickly called for former Vice President Joe Biden. None of the state’s congressional races were close, and Democrats seemed assured of recapturing all nine of the state's House seats.

But, the shape of the presidential race and the battle for the control of the Senate remain murky as the election officials across the country deal with the unprecedented numbers of mail-in and absentee ballots.

As the early returns rolled in, both President Donald Trump and Biden racked up predictable victories in their base states. The Associated Press called Vermont for Biden and Indiana for Trump within minutes of the polls closing.

At the top of each hour, AP and TV networks called another round of uncompetitive states: Nebraska for Trump, New York for Biden.

As the night wore on, it became clear that the presidential race was settling into a slow, ballot-by-ballot grind in three key states: Michigan, Pennsylvania and Wisconsin. Trump’s upset victory over Hillary Clinton in 2016 was based on his narrow victories in these three traditionally Democratic states. By midnight Tuesday, all remained too close to call, with hundreds of thousands of ballots still uncounted.

Speaking to supporters at a drive-in rally in Wilmington Delware, Biden expressed confidence but stopped short of declaring victory. "I'm here to tell you tonight we believe we are on track to win this election," he said.

But he added, "it ain't over until every vote is counted," and it may still take a few days to declare a winner. As supporters in cars honked their horns, Biden urged them to "keep the faith guys, we're gonna win this."

Trump strode to a podium at the White House shortly after 2 a.m., touting his wins in key states like Ohio and Florida and saying his shrinking leads in battleground states as vote counting continues is "fraud on the American public."

He said he would go to the Supreme Court to stop counting votes.

"We don't want then to find any ballots at 4 o'clock in the morning and add them to the list," Trump told the crowd of supporters. Moments later, Vice President Mike Pence said he believes the margins Trump has already posted will be enough for victory and "while the votes continue to be counted, we are going to remain vigilant."

In neighboring Rhode Island and New Hampshire, incumbent Democratic Sens. Jack Reed and Jeanne Shaheen were quickly declared to have been re-elected. But the battle for Senate control rolled on in other states, including North Carolina, Arizona and Maine – Republican seats Democrats were hoping to flip.

Senate Republicans went into the night with a 53-47 majority in the Senate but with Democrats seeing a strong chance to win back control of the chamber. Senate Majority Leader Mitch McConnell of Kentucky held his seat, declared the winner early in the evening despite Democrats pouring millions of dollars into the campaign coffers of his challenger, Amy McGrath. South Carolina Sen. Lindsey Graham, also a Republican, was also projected to defend his seat against his well-financed challenger, Jamie Harrison.

Arizona —— the first Trump state of the night that Biden was able flip — turned out to be a bright spot for Democrats. The state also elected Democrat Mark Kelly to the Senate, unseating Republican Martha McSally.

Republicans picked up one Senate seat in Alabama as Republican Tommy Tuberville ousted incumbent Doug Jones.

In Georgia, neither incumbent Sen. Kelly Loeffler nor Democratic challenger Raphael Warnock would cross the 50% threshold required to avoid a runoff, meaning that seat will not be decided until January, which could leave Senate control undecided until then.

Massachusetts was on a path to set a record for voter turnout in this election, but with the massive wave of early voting and mail-in ballots, polling places were not overwhelmed on election day.

Lawyers for Civil Rights – which played a key role in organizing “election protection” poll monitors with other liberal groups – said late Tuesday that while there had been scattered incidents of voter intimidation and aggressive electioneering at polling places around the state, there were not major breakdowns in voting or wide swaths of ballots discarded.

Across the country, voters were expected to shatter turnout records. Despite the turnout, Tuesday’s voting appeared largely free of any major problems — despite being held during a deadly pandemic that has killed more than 230,000 Americans. There also were no signs of large-scale voter intimidation efforts or clashes at the polls, as some had feared, given the intensity on either side of the hotly contested race between Trump and Biden.

Massachusetts voters approved a ballot question that requires car manufacturers to share wireless vehicle repair data with car owners and independent repair shops. It is the first of its kind in the nation, and there is likely to still be a legislative fight in the state house around the measure's implementation. With about 80% of the vote counted, opponents outnumbered supporters for a second ballot question to convert the state to ranked-choice voting, but that race had not yet been called. Supporters of the measure conceded the race.

The Associated Press contributed to this report.