HARRISBURG, Pa. (AP) — Giddy if exhausted, Hillary Clinton embarked on a post-convention Rust Belt bus tour just hours after becoming the first female presidential nominee of a major political party.

The celebratory mood quickly evaporated amid fresh revelations that hackers had breached a program used by her campaign and Republican nominee Donald Trump promised to sharpen his barbs.

"Remember this," Trump said during a rally Friday in Colorado Springs, Colorado. "Trump is going to be no more Mr. Nice Guy." And for the first time he encouraged his supporters' anti-Clinton chants of "lock her up."

"I've been saying let's just beat her on Nov. 8," Trump said, "but you know what? I'm starting to agree with you."

About an hour later, Clinton aides acknowledged that a hacking attack that exposed Democratic Party emails also reached into a computer system used by her own campaign. The FBI said it was working to determine the "accuracy, nature and scope" of the cyberattacks.

Campaign spokesman Nick Merrill said the newly disclosed breach affected a Democratic National Committee data analytics program used by the campaign and other organizations. Outside experts found no evidence that the campaign's "internal systems have been compromised," Merrill said, but he gave no details on the program or nature of the attacks.

Partnerships with modern e-commerce companies can allow sophisticated tracking, categorization and identification of website visitors and voters.

President Barack Obama and cybersecurity experts have said Russia was almost certainly responsible for the DNC hack. The House Democratic campaign committee reported Friday that its information had been accessed.

The developments followed the leaking of DNC emails earlier in the week that pointed to a pro-Clinton bias by party officials during her primary contest against Bernie Sanders. In the furor that followed, party chairwoman Debbie Wasserman Shultz resigned just as Democrats launched their convention.

Clinton and her running mate, Sen. Tim Kaine of Virginia, will attempt to return attention to their positive economic message on Saturday, with campaign stops through economically struggling areas of Pennsylvania and Ohio.

"When we take that oath of office next January, we know we can make life better. We know we can create more good jobs," she told voters gathered at an outside market in Harrisburg, Pennsylvania.

Clinton cited an economic analysis by economist Mark Zandi, a former economic adviser to 2008 Republican presidential nominee John McCain, that found more than 10 million jobs could be created in her first term if her economic proposals were put in place. Zandi's analysis of Trump's plans found they would cost the country 3.5 million jobs and lead to a "lengthy recession."

Joined on the bus tour by her husband, Bill Clinton, Kaine and his wife, Anne Holton, Clinton stopped at a toy and plastics manufacturer in Hatfield, Pennsylvania, where she and Kaine cast Trump as a con artist out for his own gain.

"We don't resent success in America but we do resent people who take advantage of others in order to line their own pockets," Clinton said.

Trump is also focusing on Ohio and Pennsylvania, two states where he might make headway with blue-collar white men. That group of voters has eluded Clinton and may be a hard sell after a Democratic convention that heavily celebrated racial and gender diversity.

Clinton is playing up economic opportunity, diversity and national security. Democrats hammered home those themes this week with an array of politicians, celebrities, gun-violence victims, law enforcement officers and activists of all races and sexual orientation.

Their goal is to turn out the coalition of minority, female and young voters that twice elected Obama while offsetting expected losses among the white men drawn to Trump's message.

Democrats continued contrasting their optimistic message with the more troubled vision of the state of the nation presented by Trump and others at the GOP convention a week earlier.

Kaine called the "very dark and negative" event a "journey through Donald Trump's mind."

"That's a very frightening place," he told thousands of supporters in Philadelphia.

Clinton told voters that they faced a "stark choice," calling the coming election the most important one in her lifetime.

"This is a moment of reckoning for our country. I don't recognize the country that Donald Trump describes," she said.
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Lemire reported from Colorado Springs, Colorado. Associated Press writer Eric Tucker in Washington contributed to this report.