WASHINGTON (Reuters) - Democratic presidential candidate Joe Biden took the lead over President Donald Trump in the battleground states of Pennsylvania and Georgia for the first time on Friday, putting him on the verge of winning the White House.

Three days after polls closed, Biden has a 253 to 214 lead in the state-by-state Electoral College vote that determines the winner, according to most major television networks. Winning Pennsylvania's 20 electoral votes would put the former vice president over the 270 he needs to secure the presidency.

Biden would also win the election if he prevails in two of the three other key states where he held narrow leads on Friday: Georgia, Arizona and Nevada. Like Pennsylvania, all three were still processing ballots on Friday.

With his re-election chances fading, Trump escalated his baseless attacks on the results, appearing at the White House on Thursday evening to falsely claim the election was being "stolen" from him. His campaign is pursuing a series of lawsuits across battleground states that legal experts described as unlikely to succeed in altering the election outcome.