On Saturday, Sen. John McCain campaigned for GOP senate candidate Carly Fiorina, telling a group of people gathered at the Veterans Museum in Balboa Park that Fiorina “will never wave the white flag of surrender the way that Barbara Boxer has tried to do every single time we have been in a conflict.”

“Barbara Boxer is the most bitterly partisan, the most anti-defense Senator in the U.S. Senate today,” McCain added. “I know that because I have had the unpleasant experience of having to serve with her.”

In an ABC News Nightline interview scheduled to air tonight, McCain further criticized Boxer, saying that there was “no Republican that will work with her.”

“ [Working with Boxer] has been an unpleasant experience because Barbara Boxer personalizes the political discourse that we have and that’s why she’s had so very little effect of any kind in the political process,” said the former Republican presidential nominee.