Democratic candidate Joe Biden is closing on Donald Trump in tense vote counts in Pennsylvania and Georgia, two states that the current occupant of the White House cannot afford to lose if he is to keep alive his hopes of a second term.

Iran PressAmerica: Biden is piling up votes through the night and all day as counting goes on in the two states, racking up huge margins among mail-in ballots favored by Democratic voters.

As the counting results continue, Trump's allies launched legal challenges and floated conspiracy theories as Trump tweeted "Stop the Count!"

Tight races are also going into overtime in two other states that could influence the destiny of the race, Nevada and Arizona. Biden so far has 253 electoral votes and the President has 213, according to CNN.

Pennsylvania, the state that could take Biden over the 270-vote threshold needed to win the presidency, could complete most of its outstanding counts on Thursday or Friday, officials there said. The former vice president is only behind Trump by a little less than 60,000 votes.

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