Total fluke, right? Actually, no. This is the third poll in two months, per FiveThirtyEight, to show Johnson at 10 percent or better, which is unsurprising when you look at other data. For instance, a new NBC survey finds that 37 percent of adults say they dislike Hillary Clinton while another 21 percent say they “hate” her. At 39/24, the numbers are worse for Trump. More than 40 percent in two different national polls released over the last week claim they’d consider voting third-party this year and the Libertarian Party may be the only one capable of attracting protest votes from both the left and the right. At this point, it barely qualifies as news that Johnson is in double digits. How could he not be?

What qualifies as news in the new Morning Consult data is the partisan split. In theory, Johnson’s riding high because small-government conservatives are defecting en masse from a Trump-led GOP. In practice, nope. It’s more complicated than that.

Johnson draws a higher percentage of Democrats than he does Republicans. Not only that, but he’s killing Clinton among independents, with Trump pulling nearly twice as much indie support as Hillary thanks to Johnson siphoning off votes. In fact, Trump actually does a few points better among his own party than Clinton does with hers, raising the question of how exactly it is that she leads overall here. (She leads Trump 42/40 without Johnson in the race, meaning that his inclusion actually improved her lead over Trump slightly.) I can’t see the crosstabs, which are behind a reg wall, but Morning Consult’s sample must contain a lot of Democrats. Either that or Trump has an enormous lead over Clinton among independents head-to-head and actually loses a bit of his margin once Johnson enters the race.

It’s a strange data set, but the basic points are familiar. One is that there are tons of undecideds still out there, partly because it’s early but doubtless also due in part to the fact that both nominees are repellent to more voters than tends to be the case in presidential elections. Another is that independents in particular are looking around for “outsider” candidates, with two to choose from this year in Trump and whoever ends up being nominated by the libertarians. And third and most obviously, Hillary, even more so than Trump, has a ton of work to do in unifying her party. It’s no great leap for #NeverTrump conservatives to swing around behind Johnson, despite his terrible open-borders policy on immigration and leftist approach to questions of religious liberty, because he’s a small-government advocate in a race between two authoritarians. For Bernie Sanders fans, that leap is longer. Sanders’s movement is supposed to be mainly about what the left delicately describes as “distributive justice.” Bernie’s a class warrior who’s going to use government to right economic wrongs; Gary Johnson is, er, not. If you like the idea of an avowed (rather than tacit) socialist in charge of the federal government, the transition from Sanders to Johnson isn’t an obvious one.

But that assumes that Bernie fans prefer him to Hillary for policy reasons, especially economic policy, and that may not be true. Some do, of course. In particular, they may prefer him because they’re wary of Clinton’s hawkish tendencies; the libertarians do have something to offer them on foreign policy. Other Sanders voters may prefer him to Clinton because he’s “anti-establishment.” If you’re one of those, and you can’t stand Trump, then sure, a none-of-the-above candidate like Johnson makes sense. One of the lessons of the GOP primary, seen most vividly with Trump’s dominance among the type of southern evangelical “conservatives” who were supposed to prefer Cruz, is that policy is less important to many voters than other intangibles are. If you’re a lefty who’s disaffected by “the system,” why wouldn’t you cast a protest vote for libertarians?

If I’m right about some lefties looking for an anti-establishment option, it’s hard to believe that a Mitt Romney candidacy would do anywhere near the numbers among Democrats that yesterday’s poll projected. Who, after all, embodies “the system” better than Mitt, apart from Hillary Clinton herself? But then, Johnson’s numbers are destined to crumble too as the election creeps towards fall. I think there’s a critical mass of support, probably in the ballpark of 20 percent, at which undecideds will give serious thought to voting for a third-party candidate in order to send a message to the parties. The lower you fall below 20, though, the stronger the logic becomes that the “message” sent won’t be very loud and therefore you’re better off holding your nose and voting either Democratic or Republican. Given how many Republican leaders have already rallied around Trump and the pressure lefties will be under soon to back Hillary, there probably isn’t anywhere near 20 percent out there for Johnson. Still, though, it’s nice to have an outlet for the hardcore #Never voters of all stripes.