It has become fashionable in recent years to refer to a growing libertarian wing of the Republican Party, and Rand Paul, the Kentucky senator who announced his candidacy for the presidency Tuesday, hopes to become the first serious candidate to make that wing part of a winning primary coalition.

Perhaps in a decade or two, a representative of the libertarian wing of the party will have an easy time winning the nomination. It is just unlikely to happen in 2016.

The libertarians remain too young and too few to present Paul with a realistic path to the nomination. He has to win over a much larger share of more reliable Republican primary voters, who will have considerable reservations about his policies. The other problem he faces: Many of the voters most receptive to libertarian views tend not to vote.

In one sense, you could argue that the libertarian wing of the Republican Party barely exists at all. According to a large Pew Research survey in 2014 of 10,000 respondents, 11 percent of Americans and 12 percent of self-identified Republicans considered themselves libertarian. They met a basic threshold for knowing what the term meant. But there wasn’t much "libertarian" about these voters; overall, their views were startlingly similar to those of the public as a whole.

The likeliest explanation is that "libertarianism" has become a catchall phrase for iconoclasts of all political stripes. "Libertarian" seems to have become an adjective for the liberal millennials who are more skeptical of regulations and assistance for the poor than their Democratic contemporaries. The same holds for the deeply conservative college students who may want to, for example, signal socially acceptable views about homosexuality. These "libertarians" have little resemblance to the true believers who might scare everyone else out of the room with their views on a flat tax, the Civil Rights Act and a return to the gold standard.

If we take a different tack and use issue positions, rather than self-identification, to identify libertarian voters, we still find only a small number of Republicans who consistently agree with Paul’s libertarian views. Only 8 percent of self-identified Republican-leaners in the Pew data take the libertarian position on four issues that he emphasizes: disapproval of the National Security Agency’s surveillance program; support for a more restrained U.S. role in the world; skepticism of the efficacy of military intervention; and a relaxation on drug sentencing.

These voters tend to hold relatively liberal-libertarian views on other issues. Seventy-seven percent favor same-sex marriage; 54 percent think abortion should be legal in all or most cases; and 62 percent do not believe that the police should be able to search people if they look suspicious.

But when liberal cultural politics conflicts with libertarian principles, the liberal views of these voters often prevail: 65 percent think the country should do "whatever it takes" to protect the environment; just 57 percent think the courts should interpret the Constitution strictly, as it was originally written; and 31 percent think it’s more important to control gun ownership than to protect gun rights. These voters nonetheless identify as Republicans because of their views on assistance to the poor and individual responsibility.

Overall, these voters look more like socially moderate Republicans than traditional libertarians. Perhaps the best evidence for this interpretation is that the more Republicans agree with the libertarian view on issues like marijuana or military intervention, the more liberal they get on guns, the environment, the Constitution and gay rights — even when those views conflict with traditional libertarian philosophy. Their seemingly libertarian views might just be a product of the times — they came of age during an era of liberal cultural norms and an unpopular war overseas — not a philosophical commitment to extremely limited government.

The problem for Paul is that these voters remain a distinct minority in the Republican Party. Two-thirds of Republican leaners disagree with the libertarian view on at least two of the four key issues mentioned above.

If these issues were trivial, perhaps it wouldn’t matter. But national security seems sure to become a big issue in the election, and it will overwhelmingly work to Paul’s disadvantage. (An ad has already been made to criticize his stance on Iran.) That was not obvious a few years ago, when the main critiques of President Barack Obama’s defense policy concerned not seeking congressional authorization for intervention in Libya, the NSA program and his drone policies, where Paul was on fairly firm ground politically.

But now that the Republican critiques of Obama have turned to issues involving the Islamic State and Iran, Paul’s reputation for restraint or even isolationism could prove problematic. In a CBS News poll conducted in late March, 61 percent of Republicans said they could not vote for a Republican candidate who did not agree with their views on how to deal with the Islamic State — more than any other issue.

And Paul’s other views, such as those on sentencing or drug policy, will probably cost him additional votes, perhaps among older, Southern and evangelical voters.

To remain broadly acceptable, Paul will need to run an utterly mainstream campaign. But it is unclear whether such a strategy will excite and turn out the modest libertarian base cultivated by his father.

Just 30 percent of libertarian-leaning voters say they "always" vote in congressional primaries. As a result, the share of voters who disagree with the libertarian view on at least two of the four core issues rises to three-fourths from two-thirds among the voters who say they always vote in the primaries.

The easiest explanation is age: A staggering 38 percent of the consistently libertarian voters are ages 18 to 34. This isn’t any surprise, as Ron Paul’s strongest support came from young voters in 2012, and early polls suggest this will be Rand’s base of support as well. A recent CNN poll found Paul at 17 percent of the younger-than-50 vote, but at just 7 percent among those older than 50. Similarly, a Washington Post poll gave Paul 15 percent of the younger-than-50 vote and just 4 percent of those older than 50.

This is not the base you want to have in a primary, especially if you’re a Republican. Primary elections attract older voters, not the young. In the 2008 Georgia Republican primary, for instance, 18- to 34-year-old voters represented 13 percent of the electorate, while 55 percent of voters were older than 50.

The likelihood that Paul is counting on fairly irregular voters raises serious questions about whether a more mainstream campaign can generate high turnout on primary election days. The elder Paul aroused not just young voters’ support but also their passion by pushing for marijuana legalization, opposing the war on drugs and the war on terror, and even tapping into various conspiracy theories of the right.

It is already clear that Rand Paul will not resort to these same messages and policies. He has argued for relaxed drug sentencing, not marijuana legalization or an end to the war on drugs. He wants to audit the Federal Reserve but does not seem to support a return to the gold standard. The news media will treat him as a fairly mainstream candidate, depriving him of one of the reasons his father gained momentum on the Internet: the view that he was being intentionally suppressed by the establishment and mainstream media.

Is it possible that Paul could strike a balance between igniting a young libertarian base and appealing to the broader Republican electorate? It should not be ruled out entirely. The first two primary states, Iowa and New Hampshire — a caucus and an open contest where his father’s presidential campaign fared well — are potentially good opportunities for his campaign. It’s hard to rule out any campaign that seems to have a plausible shot to win both states.

But mobilizing the coalition necessary to win either state, and remaining a broadly acceptable candidate that the rest of the party would not unify against, will require a delicate act that has never been pulled off.

Nate Cohn, New York Times

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