MR. Joe Biden of the Democratic Party closed in on victories in Nevada and Arizona on Friday while also overtaking Mr. Donald Trump in Pennsylvania.
But there will be a recount in Georgia where Biden was also the favourite.
Trump and his team remained defiant, insisting that the election was not over yet.
The Biden camp was optimistic of adding all of the 20 electoral votes in Pennsylvania.
The former vice president was billed to deliver a major speech at press time.
Last night, Biden was leading with 41,302 votes in Arizona,13,662 votes in Pennsylvania,1,553 votes in Georgia and 20,137 in Nevada
Biden had 264 electoral college votes yesterday; six short of the 270 needed to win the race.
There were permutations that if he won Pennsylvania, he would have gained 20 votes and would no longer need either Arizona or Nevada.
But if he wins Arizona – which has 11 electoral college votes – and Nevada – which has 6 – he no longer needs Pennsylvania.
Trump, on the other hand, continued to talk tough even when the odds kept mounting against him.
He vowed to continue to “pursue this process through every aspect of the law to guarantee that the American people have confidence in our government.”
“I will never give up fighting for you and our nation,” he said.
Matt Morgan, his campaign general counsel, said: “This election is not over. The false projection of Joe Biden as the winner is based on results in four states that are far from final.
“Georgia is headed for a recount, where we are confident we will find ballots improperly harvested, and where President Trump will ultimately prevail.
“There were many irregularities in Pennsylvania, including having election officials prevent our volunteer legal observers from having meaningful access to vote counting locations.
“We prevailed in court on our challenge but were deprived of valuable time and denied the transparency we are entitled to under state law.
“In Nevada, there appear to be thousands of individuals who improperly cast mail ballots.
“Finally, the President is on course to win Arizona outright, despite the irresponsible and erroneous ‘calling’ of the state for Biden by Fox News and the Associated Press.
“Biden is relying on these states for his phony claim on the White House, but once the election is final, President Trump will be re-elected.”
Responding, Biden’s team said: “As we said on July 19th, the American people will decide this election.
And the United States government is perfectly capable of escorting trespassers out of the White House.”
The Secret Service was reportedly sending additional agents to Biden’s hometown of Wilmington, Delaware to increase protection of the former vice president as he inches closer to a potential victory.
Media reports said additional agents were being sent to Wilmington.
The Secret Service activated the group of additional agents after being notified by the Biden campaign that it planned to continue using a Wilmington convention centre for at least another day, with plans to make a major speech on Friday.