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Story highlights

Marco Rubio is riding high off a widely praised debate performance in Houston on Thursday night

He has a new-found energy in going after front-runner Donald Trump

He does not lead the race in a single Super Tuesday state where there is reliable polling

CNN —  

Marco Rubio has an ace up his sleeve going into Super Tuesday: He tends to do very well with late-deciding voters and outperform his polling numbers on Election Day.

The catch? There has to be enough undecided voters left to make up the ground he needs.

Rubio is riding high off a widely praised debate performance in Houston on Thursday night and a new-found energy in going after front-runner Donald Trump. Yet as he barnstorms the states that vote on Tuesday, with special attention on Virginia, he does not lead the race in a single Super Tuesday state where there is reliable polling. In fact, it’s not even close.

But Rubio has made a habit of closing strong in states, buoyed by voters and caucusgoers who made up their minds late in the game.

In Iowa and South Carolina, Rubio outperformed polling estimates by about 8 percentage points. Going into both races, CNN’s poll of polls had him at 15%. Rubio finished with 23.1% of the vote in Iowa and 22.5% in South Carolina.

Among voters who made up their mind the week before the election, Rubio was the top choice in both states, according to exit polls. In Iowa, 45% of voters said they made up their mind in the final week, with 29% for Rubio, 27% for Texas Sen. Ted Cruz (who won the caucuses) and 14% for Trump. Among the 55% who made up their mind before the final week, 33% were for Trump, 28% for Cruz and 18% for Rubio.

In South Carolina, 46% made up their mind the final week, splitting 28% for Rubio, 26% for Cruz and 17% for Trump (who won the primary). The 54% who decided before then were 49% for Trump, 11% for Cruz and 9% for Rubio.

Rubio finished in fifth place in New Hampshire after a dismal debate performance, losing late-deciding voters as well. But he came back in South Carolina and then also performed well among last-week deciders in Nevada.

In Nevada, where Rubio finished second at 23.9%, within the margin of error of CNN/ORC’s final poll putting him at 19%, the number of people making up their minds late was smaller. Some 30% said they picked in the last week – splitting 39% for Rubio, 26% for Trump (the eventual winner) and 24% for Cruz. Of the 70% who made up their mind earlier, Trump got 55%, Cruz 20% and Rubio 18%.

Rubio tends to perform well among voters who say electability is important to them, a core pitch of his campaign. His strategy has also been predicated on staying close enough to the front-runner without winning, assuming he’ll pick up the support he needs eventually as other candidates drop out and leave a two-man race.

“The race is very fluid at this moment,” Rubio spokesman Alex Conant said, citing candidates exiting the campaign and many Super Tuesday states not seeing much campaign advertising up to this point, as well as a concerted effort to ding Trump.

“I think there’s a ton of undecided voters out there,” he said. “I think we’re going to see a lot of movement in the polls over the next couple of days. And we’ve done well with late deciders in the past.”

But while the phenomenon is real, it’s unlikely to be enough to carry Rubio into first place anytime soon.

“The problem is it’s diminishing, so it was a third or more in the first three states, but there were fewer in Nevada,” said veteran Monmouth University pollster Patrick Murray. “As we go on and on in this race, into Super Tuesday, we’re going to have even fewer late deciders, which means he can still take one-third of late deciders, but it’s just not going to be enough considering how big Trump’s lead is in the polls.”

Murray said his organization repolled voters in Iowa after the caucuses and found that many voters who had said they would support former candidate Jeb Bush and Ohio Gov. John Kasich changed their mind on caucus day based on who they thought could win.

“The limitations are once we get down to a smaller field, the dynamic that has helped Rubio which is late-deciding voters looking for the most viable candidate doesn’t help anymore, because we’re now down to the remaining viable candidates,” Murray said. “And because of that we will see fewer voters in the next contest waiting until the last few days to make up their minds.”

Where can he win?

Of the Super Tuesday states where there’s polling, Rubio looks to be in a tough spot. In Alaska, a January Alaska Dispatch News poll found Trump at 27.9%, Cruz at 23.8% and Rubio at 6.9%, with 13.4% undecided.

In Massachusetts, a more moderate state, a WBUR poll last week found Trump leading with 40% to Rubio and Kasich’s 19% each, with 6% undecided or unwilling to answer.

In Texas, a Monmouth poll last week had Cruz leading 38% to Trump’s 23% and Rubio’s 21%, with 6% undecided.

And in Virginia, a Monmouth poll last week had Trump leading 41% to Rubio’s 27% with 4% undecided.

Veteran Quinnipiac University pollster Peter Brown said essentially that anything is possible.

“Is it possible from Rubio to pull enough votes to be competitive? Of course it is,” Brown said. “Whether he will or not is a different question. There are certainly enough voters out there.”

Brown also cautioned it’s hard to know for sure how substantial Rubio’s boost has been in the past.

“He has shown in some of the early states the ability to do well among late deciders, and that has given him better numbers than he was perceived to have, but how large a bump that is, it’s not quantifiable,” Brown said.

Rubio has had a good news cycle since Thursday, with wide, positive coverage of his debate performance and a newly revamped stump speech that went after Trump on fronts including misspelled tweets, bodily fluids and being a “con artist.”

But Murray cautions that it’s hard to move the needle much with even a great debate performance, especially so close to an election.

“What Rubio did is not going to convince any Trump voters that they’re wrong; in fact, it’s only going to further convince them they’re right – we’ve seen this time and time again,” Murray said. “The message Rubio was sending to people supporting Cruz, Kasich and (Ben) Carson. … I’m not sure how much it’s going to move the needle. It’s going to move it somewhat, but I don’t think it’ll move it 15 points, which is what Rubio needs.”