Congress is scrambling for ways to safeguard the Nov. 3 U.S. elections amid the coronavirus pandemic, with a partisan fight shaping up over a Democratic proposal to require states to offer the option of voting by mail.

President Donald Trump, seeking re-election this year, and some of his fellow Republicans have voiced opposition to expanded voting by mail, citing concern over ballot fraud — a worry that Democrats dispute.

Democrats have said election procedures will need to change this year because many voters will be reluctant to stand in long lines or enter crowded polling sites for fear of infection. In recent years, Democrats also have accused Republicans of pursuing policies in some states to make voting more difficult in a bid to disenfranchise Democratic-leaning voters.