Election 2020 updates: Biden warns of 'dark winter,' pushes masks in pandemic plan

More than an hour after Biden addressed the nation, Trump took the stage at the East Room of the White House and falsely declared victory.

"We will win this and, as far as I'm concerned, we already have won it," Trump said.

ABC News projects that he has won the states of Florida, Ohio and Texas. But votes are still being counted across much of the nation, and there are millions of mail-in absentee ballots that have not yet been counted.

Trump also claimed Democrats were "trying to disenfranchise" the millions of people who voted for him, calling it "a major fraud in our nation" and saying he "won't stand for it."

"We'll be going to the U.S. Supreme Court," he said. "We want all voting to stop."

The president does not have the power to stop vote counting, and his claims of victory and fraud were baseless.

State officials have told ABC News repeatedly that they count their votes in accordance with state law and it will take time.

ABC News has not yet projected several key swing states, including Pennsylvania, Georgia, Michigan, North Carolina and Wisconsin. In each of those states, there are significant portions of outstanding votes in Democratic areas and, in many cases, those votes were early or absentee which state election officials have said would not be fully counted immediately.

Pennsylvania's three largest counties - which sent out the most absentee ballots to voters, will continue counting their mail-in ballots through the night, and into Wednesday. 

Allegheny County has scanned and uploaded 151,022 mail and absentee ballots, less than half of the 340,000 mail-in ballots received as of this early this morning.  

In addition to finishing that process over the next few days, they will also have to process any ballots they receive between now and Friday. 

While the in-person vote could be fully uploaded Wednesday, it's likely that it will take several additional days for a full count of absentee mail-in ballots. 

Updates are continually made to their count online every 15 minutes or so. 

Philadelphia is continuing to process absentee ballots received, in addition to those that will come in between Wednesday and Friday. They won't have another update to their count until tomorrow morning, after 9 a.m. The city's mail-in vote count is not currently reflected on the state's website.

Montgomery County, the state's third largest county, will continue counting through the night, and is not expected to provide any additional updates this evening. 

-ABC News’ John Santucci, Adam Kelsey, Benjamin Siegel and Alex Hosenball

Biden will pick up at least one of Maine's four electoral votes, ABC News projects.

Maine allocates electoral votes based on both the statewide result and the results in the congressional districts, so the electoral votes are not allocated all at once.

North Carolina requires a sample audit count to ensure the reliability of election results tabulated by a machine, so following the general election, the State Board of Elections will randomly select precincts, early voting sites and ballots to be counted by hand in each county.

The precincts will be audited beginning at 11 a.m. on Wednesday. The audit is a comparison of the machine counts with hand-to-eye counts completed as a test to ensure voting equipment read the voter's choices accurately.

All mail-in votes postmarked by Nov. 3 will be accepted through Nov. 12. This date was extended at the request of the state board due to an increase in volume and concerns over Postal Service. 

Local election boards will certify votes on Nov. 13 and the state board will certify on Nov. 24

-ABC News’ John Santucci and Tonya Simpson