Top GOP Senator Says Party Can't 'Stonewall' Hillary Clinton's Supreme Court Pick

— -- The Republican chairman of the Senate Judiciary Committee, Chuck Grassley of Iowa, said his party can't obstruct Hillary Clinton's Supreme Court pick if she wins the presidency.

Speaking to reporters Tuesday, Grassley, who is running for re-election this year, pushed back against Sen. John McCain's suggestion on Monday that Republicans would be "united" against a Clinton nominee for the Supreme Court.

"If that new president happens to be Hillary, we can't just simply stonewall," Grassley said.

Asked about McCain's comments on a Philadelphia radio show, Rachael Dean, McCain's communications director, said McCain will "thoroughly examine the record of any Supreme Court nominee put before the Senate and vote for or against that individual based on their qualifications, as he has done throughout his career."

Grassley and other Senate Republican leaders have not considered President Barack Obama's nominee, Merrick Garland, to replace the late Justice Antonin Scalia, insisting that the vacancy on the nation's highest court should be filled by the next president.

"I think we have a responsibility to very definitely vet ... whoever nominee that person puts forward. We have the same responsibility for Trump," Grassley said.

"We will very clearly vet ... and once that's done, make a decision whether we'll vote for or against," he continued.

Progressive groups and Democrat Patty Judge, who is running against Grassley for his seat, have criticized him and other Republicans for refusing to act on Garland's nomination.