U.S. Senator of Kentucky Rand Paul speaks onstage during "Why Can't Tech Save Politics?" at the Vanity Fair New Establishment Summit at Yerba Buena Center for the Arts on October 8, 2014 in San Francisco, California. (Michael Kovac/Getty Images For Vanity Fair)

“The Republican Party brand sucks,” Republican Rand Paul said in Detroit last week.

This was candid, and correct: Though the GOP will make gains in Tuesday’s midterm elections, its long-term prospects are grim because young people, women and minorities don’t feel welcome in the party.

But Paul thinks he can make the Republican brand stop sucking, or at least suck less. The senator from Kentucky is preparing a 2016 presidential run based on a gamble that his libertarian policies can appeal to young people and minorities. And a poll out this week gave a big boost to Paul’s rationale for running.

The Institute of Politics at Harvard’s Kennedy School released a survey of millennial voters showing that this 18- to 29-year-old demographic, a rock-solid Democratic constituency a few years ago, is now up for grabs. If this is true, the Republican Party, in the right hands, might be able to defuse the demographic time bomb ticking at party headquarters.

When Barack Obama won the presidency in 2008, he did it with 66 percent of the votes of those under 30, a modern record. In his reelection, he captured a still-impressive 60 percent of the 18 to 29 crowd. But in the Harvard survey, a majority of those young people likeliest to vote nationwide on Tuesday prefer a Republican Congress to a Democratic one, 51 percent to 47 percent. In 2010, the same survey found a Democratic advantage of 55 to 43 among likely voters.

“For the first time in about a decade, young people want to have a conversation with both parties,” John Della Volpe, director of the Harvard poll, told me. At the same time, “you’ve seen the emergence of a libertarian streak” among millennials, the pollster said. This means “there’s a lot of opportunity for Rand Paul” if he can tap even a fraction of the youth involvement Obama did. Paul (or any Republican) wouldn’t have to win a majority of young voters to win the presidency. They’d just have to cut their losses to below 10 percentage points. “When you put that perspective on it, I don’t think it’s that crazy,” Della Volpe said.

Particularly when you look at how dramatically they turned against Obama. A majority of millennial voters now disapprove of Obama’s job performance. More ominous: Only 49 percent of young Hispanics, a crucial demographic for Democrats, say they approve of Obama — a stunning turnaround from 2009, when 81 percent supported Obama.

The problem seems to be Obama himself more than his policies. Young voters, still relatively liberal, said they trust the Democrats more than Republicans on all issues they were asked about: the economy, foreign policy, immigration, race relations and health care. But they disapproved of Obama’s handling of each one.

Peter Levine, a specialist in youth civic engagement at Tufts University’s Tisch College, agreed that the likeliest figure to benefit from the shift is Paul, whose candidacy “would scramble things up in a pretty interesting way.” Levine said it’s “not out of the question” that Paul could best Hillary Clinton among millennial voters in a theoretical matchup.

That is, if Paul doesn’t squander the opening Obama gave him. The Democrats’ loss of millennials’ support doesn’t necessarily mean a Republican gain. Distaste among the young for congressional Republicans (72 percent) is greater than disapproval of either the president or congressional Democrats.

Paul says he can “reach out to whole new audiences” of young people and racial minorities with his plans to reduce drug sentences and low-tax “economic freedom zones” in depressed urban areas. But though millennial voters lean toward his libertarian views on social issues and foreign policy, they don’t share his antipathy toward big government.

The bigger danger to Paul is that, in trying to win the Republican nomination, he’ll lose the qualities that make him appealing to millennials. Unlike his gadfly father, he has positioned himself as a conventional politician, taking have-it-both-ways positions on immigration and same-sex marriage. He has inched away from his isolationist foreign policy (supporting airstrikes against the Islamic State terror group). He has become a party-line Republican on the campaign trail, embracing GOP candidates of all stripes in some 30 states. His RandPac has been pouring in money to help veteran Republican Sen. Pat Roberts fight off an independent challenger in Kansas. On Monday, Paul will campaign for fellow Kentuckian Mitch McConnell, the old-guard Republican in line to become Senate majority leader.

Paul has a chance to save his party — if he doesn’t become part of what makes the Republican brand suck in the first place.

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