Story highlights David Plouffe was a top campaign aide to Obama eight years ago

He says Bernie Sanders has no chance to defeat Hillary Clinton

The Axe Files, featuring David Axelrod, is a podcast distributed by CNN and produced at the University of Chicago Institute of Politics. The author works at the institute.

Chicago (CNN) Eight years after helping Barack Obama defeat Hillary Clinton in the Democratic primary, David Plouffe believes Clinton has the party's 2016 nomination locked up and that she should be rooting for Ted Cruz to emerge as her general election opponent.

After joking that he has as much chance as Bernie Sanders to win the Democratic nomination -- "I mean zero" -- Plouffe warned that Clinton, whom he supports this time around, has some concerns of her own to address, he cautioned. In particular, Plouffe told David Axelrod on "The Axe Files," a podcast produced by CNN and the University of Chicago Institute of Politics, Clinton's lack of support among young voters is "a huge problem for the campaign" and that she faces a challenge in igniting a passion among prospective voters.

"Hillary Clinton's biggest challenge is can she create the passion on the ground, both to get the turnout and the organization to bring people out?" he said.

Organization will matter in the general election, where Plouffed said Clinton would be better off if Cruz win the GOP nomination.

"I'd prefer to run against Cruz," Plouffe said. "With Cruz, I think you know what you're dealing with. He doesn't have a lot of elasticity. I still think you can win comfortably if you run a strong race and get good turnout. If not, you know, a Cruz-Clinton race could get uncomfortably close. But with Trump I ... just think that the execution and prosecution of the campaign day-to-day will be gruesome."

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