Well, here it is. At long last, a survey from NBC News and the Wall Street Journal showing someone besides Donald Trump with a big lead in the Republican nomination race. Now it's Ben Carson 29, Trump 23. What's more, Carson's support jumps to 50 percent once voters' second choices are added into the mix. It's the end of an era!

Ha ha, no. Haven't you been paying attention to 2015 at all? The only sure thing is that every single natural prediction political observers might be inclined to make will be proven wrong.

Last week, we noted that Trump's held a lead in the Real Clear Politics polling average for more than 100 days -- 108 at this point. But that's probably a less interesting number than this one: 97. That's the number of days that Trump has held at least 20 percent of the vote in the polling average. For Carson, it's 18.

What's happened in the polling isn't that Trump's getting much weaker -- it's that Carson has seen a surge. A recent poll in Iowa offers a bit more insight, if one were to foolishly extrapolate to the national picture. In that state, where Carson now leads, Trump's base of support is much more solid. About a third of Trump supporters say they won't change their minds, versus half that number who are as firmly committed to Carson.

We've seen the up-and-down here before -- Carson closing in on Trump and Trump holding on. It's fascinating to see how his lead differs nationally versus the early-voting states of Iowa and New Hampshire. In Iowa, Carson's beating him soundly. Nationally, they're evenly matched. In New Hampshire, it's all Trump.

It's three different trend lines. Compare that to Hillary Clinton. Her leads nationally and in the two early states slipped -- and are now recovering. It shows a very different race.

In fact -- rather amazingly -- it's the Democratic field that is consolidating on to one candidate, not the Republican one. We had predicted that Clinton would see a big boost in the polls once Joe Biden decided not to run, and sure enough, she has. In NBC/WSJ polling, she's now up 31 points on Bernie Sanders -- two-to-one -- compared to a 20-point lead a few weeks ago. (She's about where the Clinton-plus-Biden line would have predicted she'd be.)

On the Republican side, it's much more of a scramble.

There's Trump, floating around the top, and the Carson surge past him. Carly Fiorina plunging, and the second tier of candidates sort of hovering at that level. The Democratic field had six candidates at the time of its first debate -- one of whom, Larry Lessig, wasn't included on the stage, and with the possibility of Biden out there. The field is now three.

The Republican field has actually lost fewer candidates, in part because the people at the front of the pack are so much more within reach.. Clinton is up 31 points. Fiorina is closer to Ben Carson than that. Why drop out with 3 percent support if that much support still puts you in the middle of the pack?

The tricky thing at this moment is that even consolidation won't do much for the one-time top tier of the GOP. If Jeb Bush and Carly Fiorina and John Kasich and Chris Christie and George Pataki drop out, throwing their support to Marco Rubio, Rubio goes from 11 percent support in this new poll to ... 28 percent, still one point behind Ben Carson.

That's now, in this moment. This poll was conducted mostly before the third debate, so maybe Rubio is actually doing better than this. But it's also comparing him to Ben Carson who, unlike Donald Trump after these 108 days, looks more like a 2012 boom-and-bust candidate. It's feasible that this Carson surge will be met by a Carson slide, in the manner of Rick Perry and Herman Cain four years ago. Leaving the one candidate with a consistent level of support back at the front of the pack: one Donald Trump.

But, again: Political predictions in 2015 are a fool's errand.