Bobby Jindal, the governor of Louisiana, also took to Twitter to defend McCain.

Former Texas governor Rick Perry went still further, calling for Trump to withdraw from the presidential race. “His comments have reached a new low in American politics,” Perry said in a statement. “His attack on veterans make [sic] him unfit to be Commander-in-Chief of the U.S. Armed Forces, and he should immediately withdraw from the race for President.”

McCain, who made his war record a cornerstone of his 2008 bid for the US presidency, has made it no secret he’s not a fan of Trump’s. “He fired up the crazies,” McCain said after a recent Trump rally.

Trump slightly backtracked on his comments via his Twitter account. But then quickly resumed his offensive on McCain.

To date, Trump’s mouth has lost him numerous corporate partners, including Macy’s and PVH Corp., which made his shirt and tie collection. This time it could cost him in the Republican primary polls, too.

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