Republican US senate candidate in Pennsylvania sues over provisional ballots

WILMINGTON, Delaware (Reuters) - U.S. Senate candidate David McCormick of Pennsylvania sought a court order to allow the Republican to make mass challenges to provisional ballots in Philadelphia in a race he appears to have won, according to court papers.

The counting of the estimated 15,000 to 20,000 provisional ballots cast in Philadelphia, a Democratic Party stronghold, was scheduled to begin at 9 a.m. ET (1400 GMT) on Friday, according to McCormick's Thursday filing in the Court of Common Pleas in Philadelphia.

McCormick leads incumbent Senator Bob Casey, a Democrat, by about 34,600 votes with 98% of the expected total statewide vote counted, according to Edison Research. The Associated Press on Thursday projected McCormick had won the seat, which would add to Republicans' majority in the Senate beginning next year.

An automatic recount will be conducted if the race is decided by half a percentage point or less, which is about the margin of McCormick's lead before the provisional ballots were counted.

Provisional ballots are cast when there are questions about a voter's eligibility and then officials investigate after the election.

McCormick said he should be allowed to make mass challenges to provisional ballots with similar problems because the sheer volume of ballots will overwhelm the ability of Republican officials to do so individually.

"Plaintiffs fear that potentially non-compliant ballots may be improperly counted, compromising the fairness and integrity of the election," said McCormick's court filing.

The Casey campaign did not respond to a request for comment.

McCormick also asked the court to sequester provisional ballots cast by voters who had their mail-in or absentee ballots rejected for a defect such as a missing inner secrecy envelope, pending a ruling by the U.S. Supreme Court.

The Pennsylvania Supreme Court said those provisional ballots must be counted, but the Republican Party has appealed the case to the U.S. Supreme Court, which has not addressed the merits of the case.

(Reporting by Tom Hals in Wilmington, Delaware; Editing by Scott Malone and Jonathan Oatis)