WASHINGTON (AP/WHTM) — The Supreme Court on Tuesday temporarily blocked the counting of some mail-in ballots in Pennsylvania, an order that could affect the tight Republican Senate primary between former hedge fund CEO David McCormick and celebrity heart surgeon Dr. Mehmet Oz.

An order from Justice Samuel Alito paused a lower-court ruling in a lawsuit over a disputed 2021 local court election that would have allowed the counting of mail-in ballots that lacked a handwritten date.

McCormick currently trails Oz by more than 900 votes in the hotly contested Senate race and a recount was ordered last week by the Pennsylvania Secretary of State.

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The 3rd U.S. Circuit Court of Appeals in Philadelphia had ruled that the state election law’s requirement of a date next to the voter’s signature on the outside of return envelopes was “immaterial.”

Based on that ruling, the state had advised counties to count those ballots in the race between McCormick and Oz.

As McCormick scrounges for ballots to make up the gap with Oz, Alito’s order also could freeze a separate federal lawsuit in Pennsylvania in which McCormick is fighting to force counties to count the ballots. The decision came hours after the McCormick campaign held a press briefing announcing they would petition courts to require hand-counting of ballots in 12 counties.

The counties McCormick’s campaign is calling for a hand recount for include Erie, York, Centre, and Bucks.

A senior McCormick campaign official said Tuesday they believe a gap exists in the number of ballots cast and counted. McCormick has led in mail-in ballots for much of the count while Oz has led in the day of ballots.

McCormick’s campaign said it was targeting precincts where there was an unusually large proportion of machine-read ballots that recorded no vote in the Senate GOP primary. That could point to errors in the electronic scanners, McCormick’s campaign said.

The requested hand recount would affect 150 precincts across those dozen counties.

Prior to the Supreme Court’s ruling, an attorney for the Republican Party told abc27 that “the law is abundantly clear” when it comes to undated ballots. “In the absence of complying with the law they shouldn’t count,” said attorney Thomas King.

The Republican Party has joined Oz in fighting the undated ballot fight against McCormick’s campaign. King said following Tuesday’s appearance that officials “can’t change the rules after an election.”

Ron Hicks, an attorney for the McCormick campaign, argued Tuesday that “the Secretary of State’s ballot to the voters only says ‘did you sign and did you include in the inner secrecy envelope?'”

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The high court’s latest action on Tuesday, called an administrative stay, freezes the matter until the court can give it further consideration.

The state law requires voters to write a date on the envelope in which they mail in their ballots. However, the envelope is postmarked by the post office and timestamped by counties when they receive it.

Pennsylvania’s recount must be completed by next week and a winner will be declared by the Secretary of State’s Office no later than June 8. Oz has already declared himself the presumptive winner of the nomination.

McCormick has been doing better than Oz among mail-in ballots, and his campaign has said it counted about 860 undated Republican mail-in ballots received by 65 of the state’s 67 counties. Counting the undated ballots will not put McCormick over the top against Oz, but it could help narrow the race.

Some counties have already agreed to count the undated mail-in ballots, while others have not, saying they are waiting for legal clarity.

In any case, counties have acknowledged accepting ballots with wrong dates.

Pennsylvania’s state Supreme Court declined McCormick’s request to intervene Tuesday, just after a judge in the lower statewide Commonwealth Court heard three hours of arguments in the case.

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