Can Mitt Romney carry his ‘Big Mo’ through Super Tuesday?

Rolling up to the biggest set of presidential nominating contests so far – Super Tuesday with 10 states voting – Mitt Romney clearly has “Big Mo” on his side, that ephemeral momentum yearned for by anyone who’s ever run for office and seen their fortunes ebb and flow.

He’s won five events in a row – Michigan, Arizona, Maine, Wyoming, and now Washington State. He’s ahead in the delegate count. And he’s picked up a long string of endorsements, most recently Rep. Eric Cantor of Virginia, a leading congressional conservative and number two Republican behind House Speaker John Boehner.

“What I have seen is a very hard-fought primary. And we have seen now that the central issue about the campaign now is the economy,” Cantor said on NBC’s “Meet the Press” Sunday. “I just think there’s one candidate in the case who can do that, and it’s Mitt Romney.”

To be sure, any assertion that Romney’s nomination is inevitable may be perched on wobbly legs.

Delegates won so far are a very small portion of the 1,144 needed to be nominated. (Romney has 180, Rick Santorum 90, Newt Gingrich 29, and Ron Paul 23.)

It’s hard to tout your congressional endorsements when you’re trying to distinguish yourself from “Washington insiders” Santorum and Gingrich. (Romney has 81 endorsements by lawmakers, Gingrich has 11, Santorum has 4, and Paul has 3.)

And as for his latest caucus victory in Washington State, it was strictly a straw poll in advance of the real delegation selection exercise, which comes later. And even then, as Seattle Times columnist Danny Westneat put it, “There was some real passion on display at the GOP caucuses Saturday. Just not for the winner.”

But there’s no denying Romney’s Big Mo.

[Let us pause here for a point of political trivia: “Big Mo” is the phrase most closely associated with George H. W. Bush, who used it to crow a bit after he had won the Iowa caucuses in 1980. “Now they will be after me, howling and yowling at my heels,” he said. “What we will have is momentum. We will look forward to Big Mo being on our side, as they say in athletics.” Bush may have had Big Mo at that point, but he had to settle for second place when Ronald Reagan won the nomination and then the presidency.]

Romney won Washington State’s beauty contest convincingly, taking 38 percent of the vote while Santorum and Paul duked it out for second place with about 25 percent and Gingrich was an also-ran. Romney is 9.4 points ahead of his GOP rivals in the Real Clear Politics national polling average. And the Intrade prediction market gives him an 85 percent chance of becoming the Republican presidential nominee.

But he’ll have a real fight to keep his Big Mo through Super Tuesday.

He’s very likely to win Massachusetts (where he was governor), Virginia (because Santorum and Gingrich failed to get on the ballot), and Idaho (where one-quarter of Republican caucus-goers are Mormon). But beyond that, all bets are off.

Gingrich has said Georgia – the state he represented as House Speaker – is a must win for him, and anything but a convincing first place likely would end his campaign. (Five Thirty Eight blogger Nate Silver at the New York Times gives Gingrich a 96 percent chance of winning Georgia, and the Real Clear Politics polling average there has him ahead by 16 points.)

Nate Silver’s projections have Santorum ahead in Oklahoma and Tennessee.

For Romney, a strong second in Georgia (which is where most polls have him) and in other states, plus winning Ohio, could be the key to maintaining momentum and strengthening a sense of inevitability.

Although Georgia has more delegates than Ohio, the Buckeye State is seen as the most important among the Super Tuesday contests. It’s a Rust Belt swing state, and as the Associated Press points out, no Republican nominee has ever become president without winning the state, making it “a powerful proving ground for the men trying to show they can take on President Barack Obama.”

Santorum had been leading in Ohio polls, but the latest voter survey finds the former Pennsylvania senator and Romney dead even there.

According to a Reuters/Ipsos poll released Sunday, Romney and Santorum are tied with 32 percent support from likely voters in the Ohio Republican primary.

“This race could really go either way between now and Tuesday,” said Ipsos pollster Chris Jackson. “If Mitt Romney is able to close this out and win this race, that gives him a leg up in going all the way to the convention and winning the Republican nomination.”