If Mitt Romney wins the GOP nomination, as seems increasingly likely, he will have plenty of time to reintroduce himself to national swing voters on his own terms. But in the short term, the evidence is mounting that the bruising GOP primary, and the bipartisan attacks on Romney’s corporate background, low millionaire tax rate, caginess about his tax returns, and his offshoring, are damaging him among the broader electorate.

The Post has just released the first national polling that directly asks about Romney’s corporate past. The results:

Overall, do you have a favorable or unfavorable impression of Romney’s work buying and restructuring companies before he went into politics?

Favorable 35

Unfavorable 40

No opinion 25

Among independents, 36 percent view Romney’s work favorably, versus 37 percent who view it unfavorably.

The Post polling team also tells me that among non-college whites — a key swing consistency that is one of the main targets of the battle over Romney’s corporate past and taxes — 35 percent view his Bain work favorably, versus 38 percent who view it unfavorably. Among moderates, the numbers are 32-39.

This comes as Post polling released yesterday found that only 39 percent of Americans overall think Romney understands the problems of average Americans, versus 48 percent who don’t; those numbers among independents are 39-46.

And an NBC/WSJ poll released last week found Romney’s negatives spiking 20 points among independent voters in the last two months.

As Romney’s background and bio become better known to voters outside the GOP nomination process, they are no longer seeing Romney as merely a generic alternative to Obama. Romney’s corporate past and low tax rate “has created a gulf between him and the average voter,” Democratic pollster Peter Hart told me last week. “If you’re an independent voter not driven by partisanship, you read all the other tea leaves to decide who is going to fight your fight.”

“When he was only the opponent of Obama, he was getting the independent vote as the alternative,” Hart added. “Now they see him in full relief, and they’re saying, `This isn’t my guy.’”

Today’s Post poll shows that there are still sizable blocs of voters who haven’t formed an impression of Romney’s Bain work. So you can expect Dems to continue working diligently to define it in the public mind while Romney remains mired in a brutal and drawn out nomination battle.

* The contrasting biographies of Obama and Romney: Relatedly, don’t miss this excellent post by Jonathan Cohn on how the two contrasting life story arcs of the likely presidential contenders this fall dovetail with their policy and ideological differences, and how they will inform the politics of the presidential campaign.

Romney’s wealth is often seen as a major liability, but as Paul Begala put it the other day, it’s the contrast in the two men’s larger life stories that Dems hope will play to Obama’s advantage. This will be important.

* Strong public support for “Buffett Rule”: With Obama and Congressional Dems set to press Republicans on specific ways to implement the Buffett Rule, a new National Journal poll finds very favorable terrain for Dems:

65 percent surveyed agreed with the proposition that Congress should “establish a new rule that anyone who earns at least $1 million annually must pay at least 30 percent of their income in taxes,” while just 31 percent disagreed.

Caveat: Voters marginally prefer the GOP’s ideas for cutting taxes and regulations to the proposals Obama laid out in his State of the Union address, again confirming that the GOP economic worldview tends to have the upper hand when pollsters ask about generalities, not specifics.

Also: A large majority (64 percent) favors the Keystone XL pipeline, suggesting that Obama and Dems need to do a far better job of explaining their position to the public.

* Is Romney really that electable? Forbes’s Richard Miniter makes a pretty comprehensive case that Romney’s weaknesses as a general election candidate have been vastly understated. Cliff notes version: Romney has not yet won a primary decisively, despite vastly outspending opponents; his corporate background won’t wear well with independents; and the not-Romney GOP vote is still above 60 percent, raising doubts as to whether he can unite the GOP this fall.

As I’ve been saying, it seems possible that Romney’s weaknesses as a general election candidate have been papered over by the far more glaring weaknesses of his rivals. (fixed)

* Romney in command in Florida: The final tracking poll from the robo-firm Public Policy Polling finds Romney leading Newt Gingrich by eight points, 39-31. Interesting nugget: The attacks on Romney’s taxes may have helped Romney among Republicans by enhancing impressions of his competence.

Telephone polling, such as that from Quinnipiac and Suffolk University, has found Romney’lead to be in the double digits.

* Gingrich vows to fight to the bitter end: He says there’s no chance he’ll drop out after a Florida loss, and here’s why:

A number of factors may combine to carry the contest well into the spring: the rise of the so-called “super PACs,” which can spend unlimited amounts of money to help the candidates of their choice; new Republican rules allowing even losers to claim percentages of delegates in more than half of the contests this year; and the never-say-die ethos of the Gingrich campaign.

So it was that when he was asked here if there was any chance he would drop out upon a loss here on Tuesday, Mr. Gingrich said in a brief interview, “None,” adding, “We’ll be in every state.”

* Translating Romney’s line about “envy”: With Romney seemingly doubling down on the idea that conerns about inequality and his corporate past are driven by “envy,” Eugene Robinson boils down his core message: “Yes, I made a ton of money. You got a problem with that?”

Also, Robinson asks the question that I think will loom larger as the campaign wears on: Why does Mitt Romney want to be president, anyway?

* Obama needs to make a stronger case about ecnomic growth: Mike Tomasky counsels the President and Democrats to make a stronger case that govermnent policies designed to promote economic fairness and level the playing field will also lead to growth and prosperity.

As Tomasky writes, Dems must not cede the argument about economic growth to Republicans.

* Conservatives vow to make House GOP leadership’s lives miserable: House conservatives are vowing to keep up the pressure on the House GOP leadership to hold the line on key upcoming legislative fights, such as the payroll tax cut extension.

Interesting nugget: House conservatives believe that their positions have helped the GOP “draw a distinction between themselves and Democrats,” an assessment Dems would surely agree with.

* And a quick note to readers: The Post has just announced some changes to the comments sections: Moderation will be stricter, and you all will have better direct access to the moderators. You can read about the changes right here .

What else?