TIMELINE: Which states could tip US election and when will they report results?

Three days after Americans went to the polls to cast their votes for president, Democratic candidate Joe Biden has taken the lead in Pennsylvania and Georgia for the first time.

To capture the White House, a candidate must amass at least 270 votes in the Electoral College. Most major TV networks gave Biden a 253-214 lead over Republican President Donald Trump as of Friday morning.

Results in Pennsylvania (20 electoral votes), Georgia (16), North Carolina (15), Arizona (11) and Nevada (6) remained uncertain, according to Edison Research.

PENNSYLVANIA

Biden took the lead by 5,587 votes on Friday morning. With 95% of the estimated vote counted, Biden has 49.4% of votes against Trump's 49.3%, according to Edison.

Winning Pennsylvania's 20 electoral votes would put the former vice president over the 270 he needs to secure the presidency, according to projections by most TV networks.

Pennsylvania can accept mail-in ballots up to three days after the election if they were postmarked by Tuesday.

GEORGIA

Biden pulled ahead of Trump by 1,097 votes on Friday morning, with 99% of votes reported according to Edison. Trump needs both Pennsylvania and Georgia to win a second term.

ARIZONA

Biden's lead shrank on Thursday night when nearly 74,000 votes were reported from Maricopa County, which includes heavily populated Phoenix. Of those, Trump won 42,276 and Biden 31,700, reducing Biden's lead in Arizona to 50.1% versus 48.5%, with about 90% of votes counted.

There were at least 320,000 ballots left to be counted in the state. Maricopa County accounted for over 200,000 of the outstanding ballots, the elections department said.

NEVADA

Biden led Trump by 11,438 votes, or 0.9 of a percentage point, with about 11% of the vote left to be counted.

Nevada Secretary of State Barbara Cegavske said in a statement that about 190,150 ballots remained to be counted, with 123,554 of them being either mail-in ballots or ballots returned at drop-off locations. She said 90% of the ballots still to be counted were in Clark County, the state's largest.

All properly received ballots will be counted for up to nine days after the election, but the exact number left to be counted was unknown, Cegavske said.

The outstanding votes are mail-in ballots and those cast by voters who registered to vote at polling places on Election Day, she said.

NORTH CAROLINA

Trump led by 76,737 votes, or 1.4 points, with about 5% of the vote left to counted.

State officials have said a full result would not be known until next week. The state allows mail-in ballots postmarked by Tuesday to be counted if they are received by Nov. 12.

Reuters