Rick Santorum may think the GOP presidential primary is only at halftime, but according to Sen. John McCain, his candidacy is “irrelevant,” after last night’s triple win for Mitt Romney. “Whether Rick Santorum stays in or not, is now basically irrelevant and Mitt has a lot of ground to make up,” the Romney backer said on CNN Wednesday morning. “I’m confident he can make it up, but every day that goes by that he’s not in the general campaign is a day lost.”