MIAMI – When the empire strikes back, it hits hard. The Republican establishment is deploying every weapon and every soldier – even Bob Dole – in an increasingly desperate attempt to pulverize the Newt Gingrich rebellion. Eventually, the shock-and-awe campaign may work.

But then what? In the establishment's best-case scenario, the party is left with Mitt Romney, a candidate whose core message, as far as I can tell, seems to be: "Yes, I made a ton of money. You got a problem with that?"

It is remarkable that the well-orchestrated blitzkrieg to save Florida for Romney was designed solely to raise doubts about Gingrich's character and electability – rather than convince voters that Romney, on the merits, should be president. It makes you wonder whether the GOP luminaries supporting this guy really believe in him.

A statement issued last week by elder statesman Dole began by arguing that "if Gingrich is the nominee it will have an adverse impact on Republican candidates running for county, state and federal offices." Dole went on to criticize Gingrich as highhanded and erratic, before ending his brief missive with another dose of realpolitik.

"In my opinion if we want to avoid an Obama landslide in November, Republicans should nominate Governor Romney as our standard-bearer," Dole wrote. "He has the requisite experience in the public and private sectors. He would be a president we could have confidence in."

"Requisite experience" isn't much of a hallelujah, yet it's typical of the pro-Romney chorus that has been singing so loudly since Gingrich won the South Carolina primary. Meanwhile, the voices of some key potential choristers haven't been heard at all: Two of the most prominent Republicans in Florida, former Gov. Jeb Bush and Sen. Marco Rubio, have declined to endorse anyone for the nomination.

But what has Romney given his supporters to work with? Yes, he served as governor of Massachusetts and implemented health insurance reforms that became the model for President Barack Obama's Affordable Care Act. Yes, he earned a quarter of a billion dollars as a private-equity mogul. These resume items are supposed to be a compelling reason to send him to the White House?

Gingrich, Rick Santorum and Ron Paul have all laid out bold visions – more properly, hallucinations – of where they would take the country. But where is Romney's shining city on a hill? What's his "compassionate conservatism," his "hope and change"? What is it that Mitt Romney, deep in his heart or down in his gut, really believes in?

"Free enterprise" seems to be what he's most passionate about, but that's not really an answer to the question of core beliefs. Who doesn't believe in free enterprise? Obama would advocate a bit more regulation of markets than Romney would; Santorum and Paul, less. Gingrich, of course, wants free-market spaceships to fly us to the moon.

Obama wants to rearrange our priorities to make the nation more prosperous, competitive and humane. Gingrich basically has the same goal, except he would do it in a completely different way – and there would be a much bigger role for space travel. Santorum's policy positions add up to a return to "compassionate conservatism" and, perhaps, a war with Iran. Ron Paul wants to decimate the federal government and force the few remaining workers to surrender their computers and use quill pens.

And Romney? Well, he has a 160-page economic plan. What he doesn't seem to have is a compelling narrative about the kind of America he envisions and the road he will take to get us there.

This is not to say that he is necessarily incapable of developing such a narrative – or, for that matter, that he is incapable of beating Obama. The president and his advisers have at times done a mediocre job of telling the administration's story. They need to better explain how individual decisions, such as delaying the controversial Keystone pipeline, fit into a coherent Big Picture of where the country needs to go.

Romney has become a very good debater, and his attack lines about Obama are honed and barbed. The only reason he still has a fight on his hands for the nomination, really, is that he let his opponents reduce his argument for the presidency to a defense of how he earned and manages his great wealth.

No matter how much he claims otherwise, the fact is that few people are envious of Romney's business success. We just want to know if that's all he has to offer.

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Eugene Robinson writes for the Washington Post.

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