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 on Tuesday, hopes to become the first serious candidate to make it 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’s just unlikely to happen in 2016.

The libertarians remain too young and too few to present Senator 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 Mr. Paul’s 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; over all, their views were startlingly similar to those of the public as a whole.