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 for David Axelrod.

Kiev, Ukraine (CNN) Despite improving poll numbers, Donald Trump still faces the political equivalent of pulling an inside straight if he is to succeed to the presidency, says Karl Rove, mastermind behind both of President George W. Bush's presidential campaigns.

"Democrats have an easier path to 270 Electoral College votes than Republicans," Rove told David Axelrod on "The Axe Files" podcast, produced by the University of Chicago Institute of Politics and CNN. That advantage makes Hillary Clinton the continued front-runner in the race headed into next week's critical first debate, Rove said.

"He's got to win all the Romney states, and as you know, three of them are up for grabs -- North Carolina, he's behind; Arizona, Georgia, barely ahead. He's got to win Florida, got to win Ohio, but that only gets him to 253. He's got to find another 17, and I think he'll win Nevada, I think he'll win Iowa, but even then that only gets him to 265. And that last five, he's got to win either New Hampshire and the second district of Maine, or Pennsylvania, or Michigan, or Wisconsin."

Rove, a columnist for the Wall Street Journal, is a chairman of the Crossroads super PAC, which has thus far refused to deploy its significant resources on Trump's behalf, focusing instead on preserving Republican control of the United States Senate. The GOP entered the year in an uphill battle for the Senate, with six Republican incumbents running for reelection in blue states President Obama carried in 2012. Democrats must seize five seats, or win four and the presidency, to wrest control of the upper chamber away from the GOP.

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