His best numbers of the year, I should say, in any poll tracked by RCP. His next best showing was 36 percent in a CNN poll; that was conducted two weeks ago. His third-best showing was 35 percent in a CBS/NYT poll; that one was conducted last week. In other words, this guy is consistently racking up his best national numbers of the campaign right now, at a moment when voters are supposed to be slowly shifting to more “serious” candidates because they’re beginning to pay more attention to the race.

And that’s not all. A different pollster, Quinnipiac, has Trump ahead in Iowa too today, although by just one point over Ted Cruz. If you’re a Trump critic, cling tightly to that Selzer poll this weekend that had Cruz up 10 there. Not only is it the best evidence that Trumpmania’s beginning to fade, it’s, er, pretty much the only evidence.

Let me give you this quote from Friday before we get to the numbers:

Trump: "what the hell is Monmouth? Can anybody explain it?" You wanna take this one, @PollsterPatrick?

— Olivia Nuzzi (@Olivianuzzi) December 12, 2015

This is Monmouth:

That’s noteworthy not just for the numbers but for the methodology. Monmouth conducts its polls by telephone, not online. So far this year Trump has usually done better in online polls than in phone polls, for reasons that polling nerds continue to debate. (The Selzer poll of Iowa that had Trump down 10 to Cruz was a phone poll.) The fact that he’s doing this well despite Monmouth having used a methodology that tends to work against him is impressive.

That 13 percent jump in his support since October is impressive too. Where’s that coming from? Some of it must be from Carson supporters who are peeling off, but that doesn’t explain all of it (especially since Cruz must also be picking up Carson supporters). I think it’s a reaction to terrorism. When Monmouth asked people to name their top priority, 39 percent said national security and terrorism. Next was the economy at just 19 percent. Monmouth didn’t ask the same question in its October poll so we can’t compare directly, but it’s a safe bet that major attacks in Paris and San Bernardino plus Trump’s splashy plan for a temporary ban on Muslim visitors helped him here. That may fade if terrorism fades in the spotlight over the next two months, but at a bare minimum, this proves that Rubio’s got lots of work to do if he wants to be seen as the “national security candidate.” It’s hard to fill that role when a strongman figure like Trump is in your way. Frankly, I think that may be the biggest news here — not that Trump’s ahead but that he and not Rubio (or Christie) is really cleaning up as voters focus on natsec. Tell me he can’t win New Hampshire if that’s true.

Also worth noting:

While nearly 2-in-3 (65%) voters overall agree that Trump has the temperament to take on the role of president, there are significant differences in this view among the GOP electorate. More than 9-in-10 (94%) Trump supporters say he has the right temperament. Cruz voters are more likely to have a positive (52%) rather than negative (43%) opinion of Trump’s demeanor. Among all other Republican voters, though, 55% say Trump’s temperament is not a good fit for the presidency compared to 43% who feel it is.

Overall, 30% of Republicans would be enthusiastic if Trump won the nomination and another 37% would be satisfied. Just 12% would be dissatisfied and another 16% would actually be upset. Putting Trump’s supporter’s aside, most Cruz voters (63%) would be okay with Trump as the party’s standard-bearer. Among all other Republican voters, however, just 40% feel the same while most say they would be either dissatisfied (24%) or upset (29%) if Trump was the GOP nominee.

I bet the terrorism numbers are driving perceptions of Trump’s “temperament” too. Not only do two-thirds of voters say they’re okay with it, Trump’s favorable rating has actually improved since October — from 52/33 then to 61/29 now despite denunciations from the left and right over his Muslim travel ban. That favorable number is actually a few points higher than anyone else’s, including perennially well-liked candidates like Rubio and Carson. And as usual, Trump’s strongest support comes from voters without a college degree, where he dominates with 54 percent of the vote. That’s been true in poll after poll — he’s the blue-collar candidate, not just winning but usually dominating in that demographic. Ted Cruz, who’s hoping to inherit Trump’s voters, polls at just eight percent in that group. Instead of Monmouth telling us how many Cruz fans find Trump acceptable, they should have looked at how many Trump fans find Cruz acceptable. Plenty do in Iowa, but how about nationally?

If you’re looking to disregard this poll, as many Cruz fans are eagerly doing on social media this afternoon, no sweat. It’s a poll of registered, not likely voters, and it includes “leaners” which means it’s almost certainly overestimating how many Trump fans will actually show up for him. And it’s a national poll; at the end of the day, only the state polls really matter. Even so, for a guy who had a bad, bad weekend, this is something he can wave around tomorrow night at the debate. Exit question: Are we sure it’s terrorism that’s keeping Trump in front? If you look at the new Quinnipiac poll of Iowa that I linked up top, Cruz is within nine points of Trump when Iowans are asked whom they trust to handle terrorism and he actually leads Trump when they’re asked whom they trust to handle foreign policy. Trump leads Cruz big on two issues. One, not surprisingly, is illegal immigration. The other, which is also unsurprising if you’ve been reading polls this year, is the economy, where Trump is at 45 percent compared to just 17 percent for Cruz. (Among voters without a college degree, Trump leads 50/18.) The media continues to view Trump as a sort of one-trick pony, demagoging illegals and Muslims as necessary to build support. They keep missing the fact that, as the country’s most famous billionaire and a guy who’s talked often about bringing jobs back from China, he’s routinely viewed as the best choice among Republicans on the economy. Which means, if terrorism does quiet down and Trump loses his advantage there, he’ll still have a hugely important issue in his back pocket to buoy up his support. Doesn’t mean he’ll win but it does mean he won’t go away easily.