JOHNSTOWN, Pa. — Donald Trump picked a new fight Saturday with the bereaved father of a Muslim Army captain who gave a speech at the Democratic National Convention.

In the speech, Muslim lawyer Khizr Khan said Trump has “sacrificed nothing and no one” for his country.

On Saturday, Trump disputed that, saying he’s given up a lot for his businesses.

“I’ve made a lot of sacrifices,” Trump said in an interview with ABC’s “This Week.” “I work very, very hard. I’ve created thousands and thousands of jobs, tens of thousands of jobs, built great structures.”

He added: “Sure, those are sacrifices.”

In his speech, Khan gave a moving tribute to his son, Humayun, who posthumously received a Bronze Star and a Purple Heart after he was killed by a suicide bomber in Iraq in 2004.

Trump also reiterated his criticism of Khan’s wife, Ghazala, who, wearing a headscarf, stood silently on stage during the convention speech.

“If you look at his wife, she was standing there,” Trump said. “She had nothing to say. She probably, maybe she wasn’t allowed to have anything to say. You tell me.”

Ghazala Khan has said she didn’t speak because she’s still overwhelmed by her grief and can’t even look at photos of her son without crying.

Trump’s comments sparked outrage on social media, with critics attacking him for attacking a mourning mother and assailing his remarks as racist and anti-Muslim.

Khizr Khan, father of fallen Army Capt. Humayun S.M. Khan, holds up a copy of the Constitution as his wife listens during the final day of the Democratic National Convention. | AP photo

Khizr Khan, father of fallen Army Capt. Humayun S.M. Khan, holds up a copy of the Constitution as his wife listens during the final day of the Democratic National Convention. | AP photo

But Khizr Khan’s speech also has prompted a very different type of response from Trump’s comments. During his speech, he flashed a pocket Constitution and offered to lend it to the Republican presidential nominee. Now, a pocket version of the U.S. Constitution has become a best-seller on The 52-page pamphlet, printed by the National Center for Constitutional Studies, sells for $1 and was in the Top 10 best-selling books on Amazon on Saturday, even though the version Khan used at the convention didn’t appear to be the same as the one that became popular online.

Meanwhile, Hillary Clinton responded to Trump’s comments as her campaign bus wound its way Saturday through western Pennsylvania, saying she was “very moved” by Ghazala Khan’s appearance.

“This is a time for all Americans to stand with the Khans and with all the families whose children have died in service to our country,” Clinton said. “Captain Khan and his family represent the best of America, and we salute them.”

Trump’s comments about Khan come a day after, during a campaign stop in Colorado, while holding a rally in front of military aircraft, he attacked retired four-star general John Allen and also slammed a Colorado Springs fire marshal for capping attendance at his event. The fire marshal, Brett Lacey, was recently honored as the city’s “Civilian of the Year” for his role in helping the wounded at a 2015 mass shooting at a local Planned Parenthood.

“Our commander-in-chief shouldn’t insult and deride our generals, retired or otherwise,” Clinton said Saturday on her western Pennsylvania, a largely white part of the swing state that traditionally votes Republican.

“People say all kinds of things,” Clinton said. “Hateful things. Insulting things. And sometimes because of all the static going back and forth, we lose track of where we are.”

Post-convention, it has become clear the presidential race will be fought in the struggling manufacturing towns, cities and rural farming communities of the Rust Belt.

Clinton has been trying to win back some of the white working-class voters who once made up a key piece of the Democratic Party’s electoral coalition. Trump’s anti-immigrant, anti-diversity, anti-trade message has appealed to those voters, many of them frustrated with an economic recovery that’s largely left them behind.

Clinton is playing up economic opportunity, diversity and national security. Democrats’ goal is to turn out the coalition of minority, female and young voters who twice elected Obama, while blunting some of the expected losses among white men drawn to Trump’s message.

Trump has made plans to visit some of the same areas Clinton is campaigning in during her three-day bus tour through Ohio and Pennsylvania, scheduling stops Monday in Columbus and Cleveland.

The Trump campaign swaggered out of the Republican convention, feeling bullish about the bump that gave him. Trump then barnstormed in Iowa and Colorado as the Democratic convention wound down. He’s also venturing into a pair of traditionally blue states: Maine and his home state of New York, which he has repeatedly vowed to put in play despite polling that has him well behind Clinton there.