A senior aide to President Barack Obama suggested Friday that Sen. Rand Paul would be the greatest threat to Democrats’ hopes to retain the White House in 2016.

Speaking to reporters, counselor to the president Dan Pfeiffer said the Kentucky Republican is “one of the most intriguing candidates” in the field because of his appeal to younger voters of both parties.

“He’s the only Republican I think who has articulated a message that is potentially appealing to younger Americans,” Pfeiffer said at a breakfast organized by the Christian Science Monitor. “Every other Republican running is basically just Romney-lite when it comes to younger Americans.” Rand has made reaching out to non-traditional voters a signature component of his political agenda, most recently delivering a speech Friday to the National Urban League.

As for the senator’s presidential hopes, Pfeiffer questioned whether Paul has the organization to be a real threat and acknowledged that he would have to first make it through a tough primary where some of his positions are problematic to voters. But, he added, “there’s a germ of something there.”

Among Paul’s potential rivals, Pfeiffer suggested that Texas Sen. Ted Cruz would be one of the weakest candidates Republicans could field. “I think that Sen. Cruz would be a really interesting candidate for Democrats,” he said. “He is deeply out of step with the country on a wide array of issues.”

Asked whether he would prefer to run a candidate against Cruz or Texas Gov. Rick Perry, Pfeiffer laughed, “That’s like, would you rather have ice cream or cake.”

One of the longest-serving Obama aides, Pfeiffer brushed away the suggestion that former Secretary of State Hillary Clinton, the odds-on favorite to be the Democratic presidential nominee, has tried to distance herself from Obama in recent weeks as she travels the country on her book tour.

“I don’t think that we should presume that Secretary Clinton or anyone else must agree 100% with the president on every single decision that was ever made, either before or since,” Pfeiffer said. “But she has been incredibly loyal to this president.”

“On the long list of concerns that I have in my life, political and otherwise, this is pretty low on the list,” he added. “I don’t think that she’s trying to distance herself.”

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