Donald Trump's exchange with the father of an Army captain killed in Iraq is still dominating political headlines, and it's causing more Republicans to distance themselves from their party's nominee. Josh Robin filed the following report.

It was one of the dramatic moments of a presidential campaign already filled with drama: the parents of Humayun Khan, the Muslim U.S. army captain killed protecting fellow soldiers from a suicide bomber in Iraq, speaking at the Democratic National Convention.

Sunday, Trump was asked about their appearance.

"His wife, if you look at his wife, she was standing there. she had nothing to say. She probably, maybe she wasn't allowed to have anything to say. You tell me. But plenty of people have written that," he said.

In fact, Ghazala Khan says she was too distraught to speak about her killed son.

Trump found himself on the receiving end of bipartisan condemnation, from a protest outside his offices to outrage from Brian Duffy, the national commander of the Veterans of Foreign Wars.

"Election year or not, the VFW will not tolerate anyone berating a Gold Star family member for exercising his or her right of speech or expression," Duffy said in a statement.

Fellow Republican John McCain, a decorated former prisoner of war, also denounced Trump, along with other GOP senators, though none withdrew their endorsement.

And President Barack Obama, speaking before disabled veterans in Atlanta, also spoke of Gold Star families, those who lost children in battle.

"Our Gold Star families have made a sacrifice that most of us can not even begin to imagine," Obama said. "They represent the very best of our country."

Hillary Clinton stumped with Warren Buffett in Omaha. He referenced the Red Scare of the 1950s.

"I ask Donald Trump, 'Have you no sense of decency, Sir?'" Buffett said.

Trump appeared in Ohio. He did not mention the Khan family. Instead, he predicted a disputed outcome in November.

"And I'm afraid the election is going to be rigged, I have to be honest," he said.

When it comes to the Khans, Trump tweeted:

But some question whether politically, at least, it is smart for Trump to attack the family of a solider killed in war.