False claims about voter fraud in Pennsylvania have raised concerns that former Republican presidential candidate Donald Trump may once again seek to overturn the vote there or in other battleground states likely to determine the winner next Tuesday, Reuters reports.

Trump continues to falsely claim his 2020 loss to Democratic President Joe Biden was the result of widespread fraud in multiple states that Trump lost, while he and his supporters have spread baseless claims about this election in Pennsylvania.

“This is sowing the seeds for attempts to overturn an election result that cuts against Donald Trump,” said Kyle Miller, a Pennsylvania policy strategist for the advocacy group Protect Democracy. “We saw it in 2020 and I think the lesson Trump and his allies have learned since is that they have to sow these ideas early.”

Trump stepped up his unfounded allegations that probes into suspect voter registration forms are proof of voter fraud. Some of his supporters alleged voter suppression when long lines formed this week to receive mail-in ballots.