WASHINGTON - Democratic candidate Joe Biden widened his leads in Pennsylvania, Georgia and Nevada throughout Friday (Nov 6) afternoon, closing in on the 270 electoral votes needed to win the presidency although the presidential election remained uncalled.

Pennsylvania with its 20 electoral votes may be the state that pushes Mr Biden past the threshold.

The former vice-president, who had overtaken President Donald Trump there on Friday morning, expanded his lead to 27,000 votes by Friday evening. His margin is expected to grow as mail-in ballots come in.

In Georgia, Mr Biden had a slim but growing lead - 4,000 votes as of Friday evening. The margin is nonetheless narrow enough that state officials said a recount would happen, and the race may be close enough not to be called until after the recount.

Mr Biden is now at 253 electoral votes, or 264 including Arizona's 11 votes, with multiple pathways to victory and can afford to lose a combination of certain states.

Mr Trump has 214 electoral votes and Pennsylvania and Georgia are crucial to his re-election.

The Trump campaign on Friday pressed forward with legal challenges in states where he was behind.

Pennsylvania Republicans asked the Supreme Court to stop the counting of mail-in ballots - most believed favouring Mr Biden - received after Election Day and to have those ballots segregated, in case they are invalidated later.

The party is seeking to overturn the court's ruling that mail-in ballots can be received three days after Election Day as long as they were postmarked on Nov 3.

The ballots are already segregated as part of the counting process, and Pennsylvania Secretary of State Kathy Boockvar said she did not think the ballots would affect the result unless the race was close.

In Arizona, Mr Biden's lead diminished to about 29,861 votes, but analysts said Mr Trump did not appear to be garnering enough of the votes being counted to overtake his opponent there.

The Associated Press and Fox News have already called the race for Mr Biden, but Mr Trump's campaign and protesters have contested that call.

In Nevada, Mr Biden doubled his lead from roughly 11,000 votes to 22,657.

The race in North Carolina where Mr Trump is leading has yet to be called, but Mr Biden does not need the state to win the election.

Media reports said Mr Biden was planning a prime-time address to the nation on Friday night.

Here is the state of play in the key battlegrounds as of Friday evening.

Pennsylvania (20 electoral votes)

- Mr Biden leads Mr Trump by 27,000 votes, or 0.4 point, as of Friday 10pm

- About 98 per cent of the vote is in

- About 102,500 mail ballots remain to be counted, according to the Secretary of State's website

Georgia (16 electoral votes)

- Mr Biden leads Mr Trump by 4,000 votes, or 0.1 point, as of Friday 6pm

- About 99 per cent of the vote is in

- Up to 9,000 military and overseas ballots were sent out and could still be accepted if they arrive arrive by Friday, as long as they were postmarked by Election Day

Arizona (11 electoral votes)

- Mr Biden leads Mr Trump by 26,861 votes, or 0.3 point, as of Friday night

- About 95 per cent of the vote is in

- Maricopa County, the state's largest, has about 72,000 early ballots left to process and count, 5,000 early ballots to verify and 15,000 provisional ballots to process, Washington Post cited the state's elections department as saying

Nevada (6 electoral votes)

- Mr Biden leads Mr Trump by 22,657 votes, or 1.8 point, as of Friday 7pm

- About 87 per cent of the vote is in

- About 150,000 mail ballots are left, reported the Washington Post. The state's biggest county, Clark County, has 63,000 to count. Clark County, the state's largest, expects most remaining ballots to be counted by Sunday

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