The Trump campaign, the Republican National Committee and "Black Voices for Trump" sent coordinated mass emails during the Democratic debate Wednesday attacking Mayor Pete Buttigieg for his record on race and policing in his hometown of South Bend, Indiana.

Why it matters: As Axios' Jonathan Swan reported on Sunday, top Republicans are taking Buttigieg seriously as a potential general election candidate after his breakout poll in Iowa and his rise in New Hampshire. Several top Trump advisers have raised concerns that Buttigieg is more talented than Joe Biden and that he will be harder to brand as a leftist radical than Sens. Elizabeth Warren or Bernie Sanders.

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