Could Mitt Romney and [crscore]John McCain[/crscore] turn out to be the hidden arrows in [crscore]Marco Rubio[/crscore]’s political quiver in New Hampshire?

[dcquiz] It’s no secret that Beltway wisdom still argues that the Florida senator is the most likely to win the Republican nomination, even as Donald Trump dominates most of the polls and [crscore]Ted Cruz[/crscore] surges in Iowa. But the unavoidable question for anyone betting on Rubio is: what early state can Marco win?

The Daily Beast’s Will Rahn recently pondered the question in a column and couldn’t figure out an early state that Rubio is positioned to win, thus concluding Rubio has been “overrated all along.”

The thinking is that while Cruz is well positioned to win Iowa and Trump New Hampshire and possibly South Carolina, there is no state Rubio seems particularly strong in, in part because he does not yet appear to have a robust ground game in any of the early states.

I never really understood this thinking. Rubio is in second or third place in the polling averages of each of the three early states in the presidential primary season. If Trump falters, Rubio is right there in the thick of it, particularly in New Hampshire and South Carolina. And lest we forget — and believe me, none of the Republican candidates polling at basically zero and still in the presidential race have forgotten — Rick Santorum not only didn’t lead a single poll before winning the Iowa caucuses in 2012, he didn’t even place second in a single pre-Iowa poll.

It is true that Rubio has so far not spent as much time on the ground in the early states as some of his competitors. But as the Republican race enters the final month before voters actually cast ballots, residents of Iowa, New Hampshire and South Carolina will likely begin to see much more of him.

But if Trump and Cruz continue to remain strong in the polls, as seems likely at this point, it’s not hard to imagine McCain and Romney coming off the sidelines in an attempt to change the dynamic of the race, most probably in favor of Rubio.

Now that [crscore]Lindsey Graham[/crscore] has dropped out, McCain is a free agent. It’s no secret that McCain and Romney dislike Trump and Cruz – and have no desire to see either win the Republican nomination.

Perhaps the one place they can act to stop Trump and Cruz is in New Hampshire, where both Romney and McCain remain popular. McCain won the New Hampshire primary in both 2000 and 2008, and Romney won it in 2012. Romney remains so beloved by Republicans in the state that a recent Suffolk University/Boston Globe poll found that the former GOP nominee would lead the Republican field — more than doubling second place Trump with 31 percent to the billionaire’s 15 percent — if he was in the race.

So it makes sense that McCain and Romney would get behind the most viable candidate not named Cruz or Trump as the New Hampshire primary approaches in an attempt to save the country from Republican candidates they view as disastrous. Right now, the most viable candidate not named Cruz or Trump is Rubio, though it could potentially end up being Chris Christie or even Jeb Bush if either surges in the Granite State in the coming weeks.

“I do think McCain helped Romney in ’12 and think Romney would definitely help any candidate,” former Romney political strategist Stuart Stevens told The Daily Caller in an email after stipulating that he doesn’t know who the former Massachusetts governor intends to endorse, or even if he intends to endorse in the primary at all.

“McCain and Romney, along with Lindsey Graham, remain popular in the Granite State – particularly among the more establishment GOPers,” Wayne Lesperance, a professor of political science at New England College in Henniker, N.H., explained to TheDC. “So, their endorsements, if taken together for the same candidate could help identify an establishment candidate around whom voters could rally.”

Of course, Rubio would deny he is an establishment candidate – and Lesperance sees Christie as the more likely beneficiary of a McCain-Romney endorsement. Rubio’s communication’s director Alex Conant told TheDC that the campaign has nothing to say about Rubio’s efforts to woo McCain and Romney.

But if Rubio is not a card carrying member of the Republican establishment, he is at least seen as a candidate who can bridge the establishment/anti-establishment divide. He is certainly a more acceptable candidate to Washington politicos and many longtime GOP donors than either Cruz or Trump.

And both Romney and McCain seem to like Rubio — at least there doesn’t seem to be a great distaste for him like they have for Cruz and Trump. Romney considered Rubio as his VP nominee in 2012 and has spoken highly of him. While McCain has occasionally criticized Rubio for being politically opportunistic, their relationship seems fairly amicable.

Obviously, there are some potential downsides to McCain and Romney swooping in an effort to push Rubio over the top in New Hampshire. Rubio certainly doesn’t want to be viewed as an establishment stooge, as Cruz is currently trying to paint him, and being endorsed by Romney and McCain could help forward that narrative. And as famed political prognosticator Larry Sabato told TheDC, New Hampshire voters are an independent bunch and could conceivably react negatively if it appears they are being told how to vote.

“My one nagging doubt is that endorsements usually aren’t as earth-shattering as anticipated, and especially so in New Hampshire, the home of the idiosyncratic voter,” he said.

But, he noted, “Still, I think the power of McCain and Romney combined would be considerable.”

Wouldn’t it be something if at this anti-establishment moment in the American political landscape that the most establishment of Republicans end up giving Rubio the boost he needs to win a crucial early primary state — and, in turn, the momentum to win the Republican nomination?

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