The Supreme Court’s conservative majority signaled on Monday that it may side with Republicans in a Mississippi fight over when mail ballots have to arrive. It’s a ruling that could reshape how millions vote by mail this coming November.

According to the Associated Press, the issue boils down to Mississippi’s five-day grace period, which lets election officials count mail-in ballots that are postmarked by Election Day but arrive later because of postal delays. 

The Republican National Committee and state GOP argue that federal law sets a single Election Day and that ballots must be in officials’ hands by that date— not trickling in afterward. 

Civil rights and disability groups say that’s a power grab that would punish people who did everything right but got slowed down by the mail, especially older, rural, and disabled voters who rely heavily on absentee ballots.

During arguments, several conservative justices leaned into concerns about election “finality” and the fear of late-arriving votes flipping close races. Justice Samuel Alito raised the “appearance of fraud” if a “big stash of ballots” arrives after Election Day, while Justice Neil Gorsuch pressed lawyers on how long states could keep accepting ballots under Mississippi-style rules. On the other side, Justice Elena Kagan warned that reading federal law the GOP’s way could also undercut early voting and other common mail-voting practices.

The case, Watson v. RNC, goes far beyond one Southern state. At least 13 states, including vote-by-mail hubs like Oregon and Washington, count ballots that are postmarked by Election Day but arrive later. 

A decision expected by late June will likely set the rules of the road for the 2026 midterms—and signal how far this Court is willing to go in narrowing how Americans can vote by mail.