Colorado Springs (CNN) Donald Trump on Friday abandoned his modest dismissals of the "lock her up" chants his supporters have aimed at Hillary Clinton.

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

The comments, which came in his first public appearance since Clinton ripped him in her speech at the Democratic National Convention Thursday night, marked an about-face for Trump, who in the last week has resisted joining in on his supporters' chants and instead urged them to channel their anger at the ballot box.

"You know it's interesting. Every time I mention her, everyone screams 'lock her up, lock her up.' They keep screaming. And you know what I do? I've been nice," Trump explained to his supporters in this evangelical bastion of Colorado Springs. "But after watching that performance last night -- such lies -- I don't have to be so nice anymore. I'm taking the gloves off."

There would be "no more Mr. Nice Guy" Trump vowed, ignoring his yearlong track record of pillorying Clinton on the campaign trail, including raising her husband's White House sex scandal and referring to her as a "nasty, mean enabler."

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