Defend Our Constitution, a super PAC that registered with the Federal Election Commission in late September, has spent hundreds of thousands of dollars on ads opposing McCormick, federal records show.

In a TV ad running in the Keystone State, Defend Our Constitution dubbed Constitution Party candidate Marty Selker “the choice for true conservatives” while criticizing McCormick for his ties to China as a businessman. Republicans have also sought to link Sen. Bob Casey (D-PA), the Democrat running to retain his Senate seat against McCormick, to China.

The Pennsylvania Senate race is one of the most competitive in the country this election cycle, with Casey leading McCormick by roughly two percentage points, according to a RealClearPolitics polling average. Being a key swing state, Pennsylvania may also decide the 2024 presidential election between former President Donald Trump and Vice President Kamala Harris.

Defend Our Constitution is boosting the third-party candidate, Selker, but it maintains ties to Democrats.

Filings show the firm that it paid for ads is Wavelength Strategy, a Democratic-aligned firm, Politico reported.

The super PAC also paid the North Carolina-based Public Policy Polling, which is affiliated with the Democratic Party, for polling services.

Defend Our Constitution’s address is listed as a UPS store in Washington, D.C., property records show.

Selker, meanwhile, raised a mere $11,000 at the close of September and has not paid for ads, Politico reported.

“Bob Casey and his scumbag allies can see Pennsylvania is slipping, so they’re resorting to dirty tricks and underhanded tactics to bail him out,” said National Republican Senatorial Committee spokesman Philip Letsou. “Bob Casey must immediately denounce these misleading ads and call on his allies to take them off the air.”