MANCHESTER, N.H. — Marco Rubio benefited from low expectations in Iowa. How else do you explain finishing third and getting a big bump in the polls? And before Saturday night’s debate debacle, I thought expectations might be getting too high for Rubio in New Hampshire. For example, check this out:

I just talked to a voter who thought Rubio won the Iowa caucuses. "He didn't win? So what the hell is he celebrating about?" — Chris Megerian (@ChrisMegerian) February 6, 2016

But the debate, during which Chris Christie pretty thoroughly tore Rubio apart, appears to have changed all that. It’s hard to say what people expect of Rubio now, but he’s in a pretty precarious position. Even before Saturday’s debate, Rubio’s hold on second place wasn’t especially secure, and with Rubio, John Kasich, Ted Cruz and Jeb Bush all huddled with support in the low teens or high single digits, even a small post-debate dip could push Rubio from second to third … or fourth … or fifth.

According to our polls-only forecast, Rubio has a 42 percent chance of finishing in at least second (Donald Trump has a 77 percent chance of finishing first). That leaves a 58 percent chance of Rubio finishing third or worse. In fact, both our polls-only and polls-plus forecasts give Rubio at least a 32 percent chance of finishing fourth or worse. And we don’t have any surveys in our current forecast taken entirely after Rubio’s debate stumble, so it’s possible that his chance of finishing third or worse in New Hampshire is even greater than we now calculate.

CANDIDATE FIRST SECOND THIRD FOURTH FIFTH SIXTH OR WORSE Donald Trump 77 15 5 2 1 <1 Marco Rubio 10 32 24 17 10 7 Ted Cruz 5 19 23 22 16 15 John Kasich 5 19 23 21 17 16 Jeb Bush 2 11 17 21 22 27 Chris Christie <1 2 5 9 16 69 Carly Fiorina <1 1 2 6 12 79 Ben Carson <1 <1 1 3 7 89 Percentage chance of finishing in each position, N.H. GOP primary Percentages displayed are from FiveThirtyEight’s polls-only forecast.

If Rubio finishes worse than second, the candidate most likely to beat him is Kasich. Kasich has a 30 percent chance of finishing in first or second in our polls-plus forecast and a 23 percent chance in our polls-only forecast. Rubio’s hope as the race shifts to the South is to become the mainstream Republican candidate — the alternative to Ted Cruz’s very conservative coalition and Trump’s fandom. A Kasich second-place finish in the Granite State — and the favorable press that would come with it — could greatly complicate that path. Kasich is a better fit for the more moderate wing of the GOP than Rubio, who has a very conservative record. Kasich may not be able to win, but he can take votes away from Rubio in later states.

Even if Rubio finishes third to Cruz (who has about a 20 percent to 25 percent chance of finishing at least second, depending on which FiveThirtyEight forecast you look at), it could be spun as a major blow for Rubio. New Hampshire has a lot of moderate voters and few religious conservatives, which really limits Cruz. Ironically, Cruz could get the bump out of New Hampshire with a second-place finish that he failed to get out of Iowa with a first-place finish. In addition, Cruz is far better set up in South Carolina, which has a lot of religious conservatives. After the first three contests, Cruz could have a second-place and two first-place finishes.

We also cannot forget that Rubio would probably end up third to Trump in both the Cruz and Kasich scenarios. Trump has a 77 percent chance of finishing first in our polls-only forecast and a 71 percent chance of finishing first in our polls-plus forecast. The press may be bored of Trump right now, though it also loves a good comeback story. It’s not difficult to imagine Trump taking up all the media if he wins as expected in New Hampshire.

All of this leaves Rubio in a potentially dangerous position. If Rubio finishes second, many people will probably forget about Christie’s smackdown of him Saturday night. A second-place finish would also fulfill Rubio’s so-called 3-2-1 strategy, which calls for him to finish third in Iowa (done), second in New Hampshire and first in South Carolina. It’s also quite possible that one of the legs of his three-legged stool gets kicked right out from under Rubio in New Hampshire if he finishes third or worse. If that happens, who knows how the media will go after him.

Check our our live coverage and results from the New Hampshire Primary elections.

Listen to the latest episode of the FiveThirtyEight politics podcast.