(CNN) An emotional Khizr Khan asks Donald Trump in a new Clinton campaign ad whether his son, a US solider who was killed in Iraq in 2004, would "have a place in your America?"
The ad is part of Clinton's closing message, one that her top aides hope will be uplifting and hopeful, offering an implicit contrast to the combativeness that the Trump campaign has turned to in recent weeks.
Khan, who was thrust into the national spotlight after he excoriated Trump in a speech at the Democratic National Convention, is seen at his home in the ad, looking at keepsakes from his son, Army Capt. Humayun Khan's, life.
"In 2004, my son was stationed in Iraq. He saw a suicide bomber approaching his camp. My son moved forward to stop the bomber when the bomb exploded. He saved everyone in his unit. Only one American soldier died," Khan says as video shows the father holding the flag that was draped over his son's casket.
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Khan adds, "My son was Captain Humayun Khan. He was 27 years old and he was Muslim American."
The ad then shows a tight shot of a visibly emotional Khan. "I want to ask Mr. Trump," he asks, "would my son have a place in your America?"
The ad -- titled "Captain Khan" -- will air in key battleground states, a campaign aide said Friday, including Florida, Iowa, Nevada, New Hampshire, North Carolina, Ohio and Pennsylvania.
Early in his campaign, Trump proposed "a total and complete shutdown of Muslims entering the United States," a policy that has become known as his Muslim ban. Since then, however, Trump and his aides have looked to back away from the policy, despite it still being on his website.
Khan has provided a counter to Trump since his speech at the DNC in July.
Standing next to his wife, Ghazala Khan, Khizr Khan chastened Trump for his proposed Muslim ban.
"Let me ask you, have you even read the United States Constitution," Khan, a lawyer, asked as he held his own pocket copy up. "I will gladly lend you my copy. In this document, look for the words, look for the words, liberty and equal protection (under) law."
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What cemented Khan's place in 2016 political history, though, was the way Trump responded to the speech, telling ABC the following Sunday, "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."
The interview drew instant rebuke from Democrats and Republicans, including GOP leaders who said it was unacceptable for the party's nominee to go after a Gold Star family. But Trump doubled down on the comments and tweeted later that Khan "viciously attacked me from the stage of the DNC and is now all over T.V. doing the same - Nice!"
Since then, Khan has done interviews for the Clinton campaign and Clinton regularly references him, including at the third and final presidential debate Wednesday in Las Vegas.
"He went after Mr. And Mrs. Khan, the parents of a young man who died serving our country, a gold star family because of their religion," Clinton said.
"Those other charges, as she knows, are false," Trump later responded.
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