PHILADELPHIA -- Fresh off a spirited convention, Hillary Clinton told prospective voters Friday they face a "stark choice" in November and pressed ahead with the scalding rhetoric against her Republican rival that marked many of the speeches in Philadelphia. Another distraction arose, however, as her aides acknowledged that a hacking attack that exposed Democratic Party emails also reached into a computer system used by her own campaign.

Rallying in Colorado, Donald Trump denounced Clinton's convention speech as "full of lies" and said he's starting to agree with those calling for Clinton to be locked up.

Not long after, the intrusion into a system used by the Clinton campaign came to light, first reported by Reuters. 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 voter analysis program used by the campaign and other organizations. The hackers had access to the program for about five days.

Merrill said outside experts found no evidence that the campaign's "internal systems have been compromised" but gave no detail on the program or nature of the attacks. President Barack Obama and cybersecurity experts have said Russia was almost certainly responsible for the DNC hack, and 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, party chairwoman Debbie Wasserman Shultz resigned just as Democrats were launching their convention.

Clinton is in the midst of a post-convention campaign bus tour through the battleground states of Ohio and Pennsylvania.

She told supporters in a West Philadelphia arena the coming election is the most important one in her lifetime.

"It's not so much that I'm on the ticket, it's because of the stark choice that's posed to Americans in this election," she said.

In Colorado Springs, Trump at times seemed to brush off the fierce convention-week Democratic criticism, which went so far as to question his sanity. Sounding more like a pundit than the subject of all the vitriol, he pronounced her speech "so average" and "full of cliches." But he grew harsher as his event went on.

"Remember this," he said, "Trump is going to be no more Mr. Nice Guy." And for the first time he encouraged his crowd's anti-Clinton chants of "lock her up."

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

Polls find that most Americans question Clinton's honesty. But in her convention speech and her first events afterward, her priority was to go after Trump, not ask for trust.

Joined on the bus tour by her husband, Bill Clinton, running mate Tim 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," said Clinton, addressing local officials and employees on the factory floor.

Trump is also focusing on Ohio and Pennsylvania, as states where he might make headway with blue-collar white men. That group of voters has eluded Clinton and was perhaps 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 Barack Obama while offsetting expected losses among the white men drawn to Trump's message.

Democrats contrasted 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 told CNN he found the Republican gathering "dark and depressing.'

The convention provided hours of glowing tributes to Clinton, including deeply personal testimonials from her husband, daughter Chelsea Clinton and Obama.

And Clinton offered an open hand to backers of Sanders, saying, "I've heard you. Your cause is our cause." But Trump said Friday that Sanders "sold his soul to the devil" when he -- unlike some of his loudly protesting supporters -- threw his support behind Clinton.

Lemire reported from Colorado Springs, Colorado. Associated Press writer Eric Tucker in Washington contributed to this report