As of Monday morning, more than 42 million ballots had been cast nationwide. NBC News is tracking the early vote here.
Democrats, including Senate candidate John Fetterman's campaign, filed a lawsuit Monday demanding that undated or incorrectly dated mail-in ballots be counted in Pennsylvania's election.
The lawsuit, which follows a similar complaint filed on Friday by various civil rights groups, argues that a provision in state law requiring mail-in ballots to include the date on the outside of mail-in ballot envelopes is in violation of federal law. The suit names the state's 67 county boards of election as defendants.
The latest wave of litigation comes after the Pennsylvania Supreme Court last week ordered that such ballots should not be counted, with the justices divided 3-3 on the legal question.
The plaintiffs in Monday's suit, including the Democratic Congressional Campaign Committee and Democratic Senatorial Campaign Committee, say the date requirement is immaterial and that enforcing it would violate a federal civil rights law that protects the right to vote.
Cobb County has agreed to extend the deadline for Georgia voters who did not receive requested absentee ballots, according to American Civil Liberties Union attorney Vasu Abhiraman.
The extension to Nov. 14 applies to nearly 700 voters who did not receive an absentee ballot and have not voted in person.
The move comes after the ACLU of Georgia filed a lawsuit against the County Board of Elections & Registration alleging that it "failed to timely send absentee ballots" to approximately 1,036 voters whose absentee ballot applications had been marked as issued last month but apparently were never sent.
The group had asked that all those affected be permitted an extension to return the ballots until Nov. 14 — the same deadline as military ballots.
Cobb County is one of the most crucial counties in Georgia. The increasingly diverse Atlanta suburb is home to swing voters in both parties and is seen as a key to any statewide office.