Pennsylvania Democratic Senate nominee John Fetterman said on Monday that he expects his Republican opponent, Mehmet Oz, to lead initially in the state on Tuesday night due to the sequence of vote counting.

Fetterman, Pennsylvania’s lieutenant governor, said that the GOP planned voting so that their party could “baselessly sow doubt about the election results when it suits them.”

“Counting for ballots cast by mail and early in-person cannot begin until Election Day, thanks to the GOP-controlled legislature,” Fetterman wrote in a memo, according to The Washington Post, calling the move “intentional” to help Republicans contest election results.

He continued: “Pennsylvania is one of only eight states that bans pre-processing of early mail-in ballots, forcing county officials to wait until 7 a.m. on Tuesday to begin opening returned ballots and scanning them into the system.”

The state’s Senate race is one of the tightest in the country, with Oz making gains on Fetterman in the weeks leading up to the election. The election is considered a “toss up” by the nonpartisan Cook Political Report.

Fetterman’s campaign wrote the memo to assure those considering backing him that their vote does matter, according to the Post.

President Biden has featured in Fetterman’s campaign rallies, saying on Saturday: “I know Pennsylvania well and John Fetterman is Pennsylvania.”

Former President Obama also advocated for Fetterman’s election this weekend and addressed the stroke Fetterman had earlier this year.

“John’s stroke did not change who he is, it didn’t change what he cares about, it didn’t change his values, his heart, his fight,” said Obama on Saturday.