Washington (CNN) Democratic presidential hopeful Pete Buttigieg on Wednesday warned against "going to the extreme" on important election issues a day after he was assailed by his liberal competitors at the CNN/Des Moines Register Democratic debate for being too moderate.

"It's certainly the case that I would caution against going to the extreme when we can solve big problems like delivering health care to every American without alienating half the country. But I also believe we can be very bold at a time like this," Buttigieg, the former mayor of South Bend, Indiana, told CNN's John Berman on "New Day."

"The point that I'm making to voters, to the American people, is that I'm prepared to be the boldest president we've had in a half century when it comes to big reforms, big game-changing improvements and advancements in our access to health care, education and more," he added. "And that there's a way to do it. That we can actually unite Americans around rather than chasing for the most extreme idea."

Buttigieg's comments reflect some of the most significant fault lines among the party's top tier candidates. The former mayor has presented a more centrist alternative to the progressive views of Sens. Elizabeth Warren and Bernie Sanders, whose ideas have excited liberal voters but, according to moderates like Buttigieg, risk alienating the rest of the country in a general election.

On Tuesday night, six candidates participated in the last debate before next month's Iowa caucuses, where voters will cast the first votes of this election cycle.

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