Sen. John McCain (R-Ariz) said Monday that if Hillary Clinton is elected, Republicans will unite to block anyone she nominates to the Supreme Court.

Speaking on WPHT-AM radio's "Dom Giordano Program" in Philadelphia, McCain pledged to obstruct any Clinton Supreme Court nomination for the current or any future vacancy.

"I promise you that we will be united against any Supreme Court nominee that Hillary Clinton, if she were president, would put up," he declared.

McCain said that's why it is so important that Republicans retain control of the Senate.

Given that two of the sitting justices are 80 or older, and another is 78, there is a strong possibility that the next president will have more than one high court opening to fill.

The current court has been operating with just eight members since last February when Justice Antonin Scalia died unexpectedly. Republicans have refused since then to confirm President Obama's nominee, Judge Merrick Garland, on grounds that filling the slot should be left to the next president.

In his comments on WPHT, McCain seems to have upped the ante, suggesting that if Hillary Clinton is elected, Republicans would block any Supreme Court nomination she would make.

McCain spokesperson Rachael Dean later said that McCain "believes you can only judge people by their record, and Hillary Clinton has a clear record of supporting liberal judicial nominees."

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