Four years ago it was 61 percent. I had a theory to explain the most recent drop when I started reading the poll, but now that I’ve looked at the trends over time, it just doesn’t hold up. I thought this new low was a reaction to the shutdown last fall; the first big dip in tea-party popularity came after the first debt-ceiling standoff in 2011, after all, so it would stand to reason that a new economic disruption would drive the numbers down further. Ted Cruz was on camera throughout the process promoting “defund” so tea partiers are bearing the brunt of the backlash.

Does this graph bear that out, though?

If the backlash was being driven by the shutdown, we should have seen the spike in opposition start last fall. In reality, opposition to the tea party declined a few points between September and December of last year. (On the other hand, the tea party’s favorable rating reached its lowest point yet during that span.) Another mystery: As of last September, 52 percent of Democrats opposed the tea party. As of today … 49 percent do. That number definitely should have risen, not fallen, if this was related to the shutdown.

But wait. If Democratic opposition is down since September, how is total public opposition up? Here’s a potential clue.

Moderate/liberal Republicans are split nearly evenly, with opposition among that group exceeding even opposition among independents. That is to say, what you may be seeing in the new numbers is a deepening of GOP ideological divisions, not any broader knee-jerk reaction to the shutdown among the wider population. Which, actually, makes sense: We’re on the cusp of a nasty primary season, with Mitch McConnell a prime target of the right, and we’ve spent the past six months with conservatives and establishmentarians at each other’s throats over immigration. Boehner’s been openly scornful of outside conservative groups; meanwhile, those same groups, along with establishment Super PACs, are spending tons of money trying to beat each other. (Check the graphs at the last link and you’ll see, contra Palin, just how much of an “us and them” attitude there is among groups on both sides.) Go figure that all of this would trigger a small but meaningful backlash to the tea party among centrist Republicans, enough to move the needle on overall public opposition a few points. If I’m right, then opposition will dip again once we’re past the primaries and focused on beating Democrats in the midterms. Stay tuned.