AP:

The national and state Republican parties are taking the same side as celebrity heart surgeon Dr. Mehmet Oz in Pennsylvania’s neck-and-neck GOP primary contest for U.S. Senate and opposing a lawsuit that could help former hedge fund CEO David McCormick close the gap in votes.

McCormick’s lawsuit was filed late Monday, less than 24 hours before Tuesday’s deadline for counties to report their unofficial results to the state.

In it, McCormick asks the state Commonwealth Court to require counties to obey a brand-new federal appeals court decision and promptly count mail-in ballots that lack a required handwritten date on the return envelope.

Oz, who is endorsed by former President Donald Trump, has pressed counties not to count the ballots and the Republican National Committee and state GOP said they would go to court to oppose McCormick.

In a statement, the RNC’s chief counsel, Matt Raymer, said “election laws are meant to be followed, and changing the rules when ballots are already being counted harms the integrity of our elections.”