Marco Rubio has been insisting for some time now that he will win Florida, with all of the certainty and bravado of the boxer picked as a warm-up fight for the eventual heavyweight champion. The polling has been grim; even after Jeb Bush dropped out, Donald Trump led Rubio by a wide margin.

A new poll from Monmouth University, though, suggests that the challenger might at least land a few punches. Rubio is now down 8 points to Trump — a much narrower gap than where the most recent polling average had the race this morning.

Monmouth finds that Rubio leads in the southern part of the state, his home turf. Trump has a 2 to 1 advantage in central Florida (think Tampa and Disneyworld) and a slight advantage up north.

That's one bit of good news for Rubio, hot on the heels of his big, sort-of-contested win in Puerto Rico. The other is that he's the preferred candidate of nearly half of those who've already voted — 48 percent — meaning that he's banking two votes for every one that Trump is even before Election Day arrives. We speculated last week that Trump's poll lead would mean that he'd also have a lead in the early vote, but Monmouth finds that's not the case. (There's a pretty hefty margin of error of 9.8 percent on those numbers, but still.)

There is also bad news for the Florida senator. Rubio had been getting a surge of late deciders in early contests, but it seems as though his support isn't quite as firm as Trump's. Two-thirds of Trump's supporters say they won't change their minds, versus 55 percent of Rubio backers who say the same thing.

The other bit of bad news is that, if John Kasich dropped out (finally) as did Ted Cruz (bafflingly), Rubio wouldn't necessarily win. He and Trump are essentially tied in a head-to-head match-up.

In Florida. Rubio's home state.

We're still a week away from the actual vote, so we'll likely have more polls coming that can confirm whether Rubio is seeing an actual surge of support. Make no mistake: He has to win Florida to keep running. If he can't win Florida — the state in which he should most naturally see a victory — it's impossible to see how he could cobble together enough delegates to win the nomination.

For the first time in a long time, Rubio's bragging about how he would K.O. the champ seems like something more than desperate bluster. After the week he's had, Rubio, still down 8 points, must be riding high.