President-elect Joe Biden's victory in Arizona was finalised on Monday, further cementing his win even as Donald Trump continues to make baseless claims of vote fraud.
"This election was conducted with transparency, accuracy and fairness in accordance with Arizona's laws and elections procedures, despite numerous unfounded claims to the contrary," Arizona secretary of state Katie Hobbs said during the vote's final, official certification.
The last Democrat to carry the southwestern state in the race for the White House was Bill Clinton in 1996, marking a significant shift of the US electoral map this year.
Mr Biden beat Mr Trump by just over 10,400 ballots in a state where turnout was high, and shifting demographics saw a growing population of young Hispanic voters.
The ex-vice president's win in the former reliably Republican bastion could also be attributed to suburban women attracted to his centrist approach, experts have said.
Eleven Democratic electors will meet on 14 December to formally cast Arizona's electoral votes for Mr Biden.
Meanwhile, Mr Biden's victory in battleground Wisconsin was also confirmed on Monday following a partial recount that only added to his 20,600-vote margin over Mr Trump, who has promised to file a lawsuit seeking to undo the results.
Elections challenges brought by the Trump campaign or his backers in key battleground states have largely been unsuccessful as Mr Trump continues to allege voter fraud while refusing to concede.
President Donald Trump speaks in the Diplomatic Room of the White House on Thanksgiving in Washington. Source: ABACA via AAP
"WOW, total election corruption in Arizona. Hearing on now!," Mr Trump tweeted as lawyers for the president and some lawmakers met in Arizona.
Mr Trump has also targeted legal challenges at the state of Pennsylvania, which the president won in 2016 but was flipped back to the Democrats this year.
Pennsylvania's supreme court dismissed on Saturday a Republican lawsuit that had sought to invalidate mail-in ballots in the battleground state - or to throw out all votes and allow the state's legislature to decide the winner.
The court dismissed both claims in a unanimous decision, calling the second one an "extraordinary proposition that the court disenfranchise all 6.9 million Pennsylvanians who voted in the general election."
Pennsylvania officially certified Biden's victory there on 24 November. The lawsuit had also sought to stop certification.
Mr Biden has proceeded with the transition process, despite efforts by Trump and his campaign to undo the election, and is due to be sworn in on 20 January.
