WASHINGTON (WMAL) — A Monmouth University poll of Iowans released Monday shows Scott Walker maintains a solid lead in the Iowa Republican caucus, with Trump taking second place.

But Trump’s decision to stick by the comments he made Sunday in a USA Today op-ed may knock him down.

Trump wrote, “Thanks to McCain and his Senate colleague Bernie Sanders, their legislation to cover up the VA scandal, in which 1,000+ veterans died waiting for medical care, made sure no one has been punished, charged, jailed, fined or held responsible. McCain has abandoned our veterans. I will fight for them.”

Retired Navy Vice Adm. Norb Ryan, president and CEO of the Military Officers Association of America, told WMAL that Trump’s assertion about McCain abandoning veterans is inaccurate, to say the least.

“That is just so inaccurate as to be ludicrous,” Ryan said. “If anybody has paid attention to our troops and done his best it’s Senator McCain.”

As the chairman of the Senate Armed Services Committee, McCain demanded that the full Senate debate and vote on the National Defense Authorization Act for the first time in three years, Ryan said in a statement.

“He has always been a champion for the all-volunteer-force and our nation’s veterans. Leadership is about setting an example and not words. No one has visited our troops in Afghanistan or Iraq more than John McCain. We can disagree with some of Sen. McCain’s positions at times, but we can never say he has abandoned the troops.”

If Trump doesn’t back down he may lose credibility, Ryan said.

“Every politician makes mistakes. The American public understands that because we’ve all made mistakes in our daily lives. What we respect is people who have the self assurance and the self confidence to say, ‘Yeah, I made a mistake. I apologize.'”

Copyright 2015 by WMAL.com. All Rights Reserved. (Photo: CNN)