This article is from the archive of our partner National Journal

Ahead of 2016, Rand Paul has a top voice in liberal politics concerned for the Democratic Party.

Bill de Blasio, New York City's first-term mayor, told journalist Mike Allen he thinks the Kentucky senator is the most formidable opponent for Democrats. Speaking at a Politico Playbook breakfast Wednesday morning, the mayor said his party needs to refocus its message on economic populism. Though he disagrees with Paul on a "host of issues," de Blasio said the likely presidential contender will be a force in the GOP.

"He evinces a certain authenticity that any good Democrat should worry about," de Blasio said. And as long as Paul isn't swayed by his fellow Republicans, he'll be a strong contender. "To the extent that there is a libertarian philosophy that he sticks to regardless of political convenience, I think that makes him a stronger candidate than many."

The mayor was in Washington to expound on his post-election op-ed last week, where he argued that, after a tough wake-up call in the midterm elections, Democrats must find their collective "backbone" in tackling economic inequality. Because 2014 campaigns didn't emphasize economic issues, he said, voters weren't inspired to get to the polls.

"The Democratic Party has to look in the mirror and bluntly realize that if we repeat 2014, we're doomed," de Blasio said. "We cannot win an election if our own people are not motivated."

De Blasio, who worked on Hillary Clinton's 2000 campaign for the U.S. Senate, said any serious Democratic candidate in 2016 needs to talk about economic populism, or else the person would be "unelectable." He hopes his former boss moves to her left on these issues if she runs in 2016.

"I think she should," he said. "I think it's necessary. I think a lot about her history and origins suggests it's natural for her."

As far as the other vocal proponent for addressing economic inequality in the party, Elizabeth Warren, de Blasio demurred. Though he said the Massachusetts senator is "one of the really indispensable voices in our national debate," he didn't want to conjecture on whether she should get in the race.

In the two weeks since the midterms, the progressive champion has been working to raise his national profile in the party. But despite a flurry of reports earlier this week, he won't be launching a bid for the presidency, and seems content to advise his fellow Democrats from the comfort of Gracie Mansion. Even so, it's likely de Blasio is not the only liberal worried about Paul. He's just hoping Democrats get the message before it's too late.

This article is from the archive of our partner National Journal.

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