Bill Theobald

USA TODAY

WASHINGTON — A liberal group and a newly formed veterans’ organization attempted Thursday to put Republican Sen. John McCain in a political vise between GOP presidential candidate Donald Trump and the senator’s devotion to military service.

Common Defense PAC, which registered in June with the Federal Election Commission, and MoveOn.org delivered petitions containing 100,000 names to McCain’s Capitol Hill offices, calling on him to withdraw his endorsement of Trump’s candidacy.

Before that, six veterans, including a Muslim veteran from McCain’s home state of Arizona, praised the former Vietnam prisoner of war as “courageous” and a “man of honor” in pleading with him to reject Trump.

McCain, perhaps the most prominent veteran on Capitol Hill, was derided by Trump last summer when the real estate mogul said he didn’t think McCain was a hero because he was captured by the North Vietnamese.

This past week, Trump became embroiled in another controversy when he criticized the parents of Humayun Khan, a Muslim U.S. soldier killed in Iraq. Khan's father delivered a speech critical of Trump at the Democratic National Convention.

Trump also declined to endorse McCain's re-election bid.

Trump declines to endorse Ryan, McCain in GOP primaries

The Trump-Khan feud: How we got here

McCain, who faces an Aug. 30 primary, quickly criticized Trump's comments about the Khan family.

But Wednesday in Arizona, he refused to answer questions about Trump during a sometimes tense news conference. And he did not respond to requests for comment about the petitions on Thursday. Nor was any comment immediately available from the Trump campaign.

McCain spars with media over Trump in feisty news conference

“Donald Trump and his surrogates have demonstrated that their bigotry and hate speech know no bounds,” said Nate Terani, a Muslim Navy veteran from Arizona. “And they hold no American value or ideal as sacred.”

“The commander in chief of the United States military is the leader of one of the most diverse military’s on Earth,” Terani said at a news conference in a grove of trees just north of the Capitol. “Donald Trump is a bigot and a racist and he is unfit for that position.”

Alexander McCoy, a Marine sergeant from New York who served from 2008 to 2013, said Trump had threatened to use the military for evil, abandoned our most loyal allies, and suggested he would use nuclear weapons unprovoked.

“I am done listening. I have heard enough,” McCoy said. “Sen. McCain this is my message to you: You served, you sacrificed in ways Donald Trump cannot begin to understand. You have heard enough, too.”

Jim Lyons, a Navy veteran from Rhode Island who is openly gay, said he feared the military under Trump would return to a system of “don’t ask, don’t tell” when dealing with gay service men and women.

And Mickiela Montoya, an eight-year Army veteran, described herself as a woman, a veteran, a Latina and a mother.

“Donald Trump has attacked every single one of my identities,” Montoya said. “Donald Trump is trying to change the definition of what it means to be an American.”

She described McCain as “a war hero, a fellow veteran, a father and the epitome of what it means to be a patriot.”

“Please do what you know in your heart is right,” Montoya said.​