A new Gallup poll shows nearly 6 in 10 Americans would like to see a third major party in American politics — a new high for a presidential election this century.

What people don’t appear to want, though, is the actual third-party candidates that are running in 2016.

First: The desire. Gallup shows 57 percent want a major American third party, while 37 percent say the existing two parties do an adequate job and that a third party isn’t needed.

The number calling for a third party is up significantly, from 46 percent in 2012 and 47 percent in 2008. Gallup didn’t poll this question in 2004, but in 2003, just 40 percent wanted a major third party.

And the desire for a third party isn’t even due to Hillary Clinton and Donald Trump being the most unpopular presidential nominees in modern history. It actually spiked in 2013 and has remained steady, between 57 percent and 60 percent, ever since.

Given this and the unpopularity of the two major-party nominees, it would seem a very good time for the likes of Gary Johnson and Jill Stein, who are running as the Libertarian and Green Party nominees, respectively. And both of them have polled reasonably well, compared to past third-party candidates.

But neither is threatening to make the debate stage — which would require 15 percent in the polls — and both have actually seen their support drop off some in recent weeks. In other words: Despite this pining for real third-party alternatives, they’re not capitalizing.

In national polls of a four-way race, Johnson is at 7.2 percent and Stein is at 2.3 percent in the Real Clear Politics average of polls. That’s the lowest Johnson has been since late July and the lowest Stein has been since before the summer. (And those numbers should drop further, if history is any indication, my colleague Philip Bump notes.)

Part of the reason neither has caught on is that people just don’t seem to like either of them.

Johnson, of course, has had some pretty bad gaffes recently, most notably when he didn’t appear to know what Aleppo was in a Sept. 8 interview. And polls suggest he might have paid a price. A Bloomberg poll last week showed his favorable rating at 24 percent, with 39 percent of people disliking him. Back in August, his split was an even 21-21 in the same poll.

Another poll last week, from Franklin Pierce University, showed his favorable-unfavorable split at 22-32 — after it was 24-16 just before his “Aleppo moment.”

Stein doesn’t have a similarly high-profile moment, and she isn’t as well-known as Johnson. But she too has poor numbers. Bloomberg put her split at 16-38, while Franklin Pierce had her at a less-terrible-but-still-negative 14-25. Not one poll since early August has had her favorable rating higher than her unfavorable rating.

This is actually not all that unusual, though; third-party candidates have often fallen out of favor after being around for a while. Ross Perot was moderately popular when he ran in 1992, but by 1996, Gallup had his numbers at 35 percent favorable and 52 percent unfavorable.

Ditto Ralph Nader, who was in positive (though still somewhat anonymous) territory in 2000 but had a 33-48 split when he ran again in 2004.

Johnson and Stein both also ran for president in 2012, though neither made nearly the splash that Perot or Nader did in their first runs. But both Perot and Nader had to contend with allegations that they were playing the role of spoiler, as Johnson and Stein have.

So it’s not clear whether people don’t like Johnson and Stein because they simply don’t like them or because they are potential spoilers or for some other reason.

But for however much Americans say they like the idea of third-party candidates, they sure don’t seem to like the execution of them.