Among the 3,672 reasons you’ve read and heard for David Brat’s victory over Eric Cantor, here’s one you haven’t seen. This explanation doesn’t have anything to do with Cantor palling around with lobbyists, or with Laura Ingraham’s one-liners. It’s about ideology, and it’s pretty straightforward: Self-identified conservatives in 2014 are really conservative, and they increasingly think that Republicans in Congress—Republicans in Congress, mind you—are a bunch of namby-pambies.

You want numbers? I got numbers. Last month, the centrist Democratic group Third Way released a study called “The State of the Center.” The report is not just another poll. It’s a really comprehensive and unique piece of work that yields more illuminating results than any poll. It has many elements, but here’s the part of interest to us. The group asked 1,500 Americans to identify themselves on an ideological scale of 1 to 9, 1 being the most liberal and 9 being the most conservative. Then these respondents were asked where they would place Democrats in Congress, Republicans in Congress, Barack Obama, and their ideal president. The answers are fascinating and jaw-dropping in that way that these kinds of findings about conservatives are, alas, no longer jaw-dropping.

Let’s start on the left side of the spectrum. Liberals put themselves at 3.88 on the ideology scale—that is, considerably closer to the middle (5) than to the far left (1). They put Obama at 4.23, just a little nearer the center than they placed themselves. And they put Democrats in Congress at 4.3 and their ideal president at the same spot. Takeaway: Liberals see themselves as being pretty close to where they see their political leaders, and that place isn’t all that far from the center.

Moderates saw themselves as slightly right-of-center collectively, at 5.37. Interestingly, they see Democrats in Congress at 4.08, or .92 ticks away from the dead political center of 5. But they put Republicans in Congress at 6.63, almost twice as far away from the center as they put Democrats. They placed Obama, incidentally, at 3.88—a little to the left of where they put the Democrats in Congress, but still a good .51 closer to the center than they put congressional Republicans.

Before we get to conservatives, permit me this brief methodological digression. This rating system, explains Third Way’s Jim Kessler, is a little like a Richter scale. That is, just as the difference between 7 and 8 on a Richter scale is much greater than the difference between 3 and 4 (because it’s a “logarithmic scale”), so too here it’s reasonable to think of the increments as more pronounced the farther they emanate out from the center. This is because far more people want to think of themselves as reasonable and kind of moderate than as extremist. So that .51 difference I cite in the paragraph above in moderates’ views of Democrats and Republicans in Congress respectively is bigger than it may sound.

All right. Now. Conservatives put themselves at 7.4 on the 1-to-9 scale—that is, closer to the extremist edge than to the center by almost a whole point (.8). They also put themselves more than twice as far away from the center as liberals did. They put Obama at 2.93 and Democrats in Congress at 3.42.

But here’s the most important number. Self-identified conservatives put Republicans in Congress at 5.76. In other words: Conservatives see congressional Republicans as basically on the center-right! Two years ago, when Third Way first asked these questions, self-identified conservatives put themselves at the same 7.4, but they put Republicans in Congress at 5.81. Now, the difference between 5.81 and 5.76 isn’t large, but it does mean that if anything, conservatives see congressional Republicans as a little more moderate than they did two years ago.

What does this have to do with Cantor and Brat? A lot. Conservatives—who, by the way, made up a whopping 79 percent of Republicans in the survey, while liberals made up just 39 percent of Democrats—see a moderate-ish congressional party that is selling out their core principles. And this reflects, in turn, Brat’s biggest and most fundamental criticism of Cantor, that the majority leader was a sell-out on immigration. What most of the post-outcome anecdotal analysis has been telling us is backed up precisely by these depressing and all-too-not-surprising numbers.

The upshot? Expect to see more David Brats. Yes, it’s hard to beat an incumbent. The incumbent has to screw up in some of the ways Cantor did, and most of his fellow incumbents will have taken note and cut back on the Beltway gallivanting. But the logic of these things is that the tea party doesn’t have to win many races to gain leverage. Up to Brat, the tea partiers lost five or six in a row. Now, they’ve won just one, and every Republican on Capitol Hill is so terrified that they won’t deviate an inch from the tea-party agenda. Someday, this extremism will come crashing down on them. But we’re for some rough water until then.