(CNN) Democratic presidential candidate Sen. Cory Booker sharply panned the 1994 crime bill as "awful" and "a mistake" in an interview published Thursday -- drawing a pronounced contrast with his rival Joe Biden, the Democratic frontrunner in the race for president.

"I use this word sincerely: I love Joe Biden," Booker told Huffington Post during a swing through Iowa last weekend. But the crime bill that Biden spearheaded, Booker said, "was awful."

"We should all agree with the force of conviction: That bill was a mistake," Booker added, suggesting it incentivized mass incarceration. "Good people signed on to that bill. People make mistakes. But let's hold them to that. That crime bill was shameful, what it did to black and brown communities like mine [and] low-income communities from Appalachia to rural Iowa. It was a bad bill."

The bill was one of Biden's signature legislative achievements as a US senator from Delaware and chairman of the Senate Judiciary Committee. But it has become something of a liability in the 2020 campaign, eliciting attacks from a new generation of candidates including Booker.

Biden was pressed about the bill during a campaign stop in New Hampshire earlier this month, where he told a New Hampshire voter , "This idea that the crime bill generated mass incarceration -- it did not generate mass incarceration."

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