* The race is on to define Romney’s tenure at Bain: One of the most important questions in Campaign 2012 may be this: Who will succeed in defining Romney’s tenure at Bain Capital in the public mind? The Romney campaign is already working hard to present his Bain years as proof that he understands the private sector and will bring a fresh, businessman’s eye to government, the economy and job creation.

Dems know that it could be seriously problematic if Romney successfully creates the impression that private sector experience would enable him to lift the hood on the economy and tinker around in order to get it humming again. The risk is that this could hold appeal to voters who, frustrated by government paralysis, are prepared to give up on its ability to fix the economy and create jobs. And so Dems know it’s imperative that they define Romney’s Bain years as emblematic of the sort of predatory and heartless capitalism that led to the economic crisis and has sparked rising public anger at inequality and lack of Wall Street accountability.

Romney’s team is emphasizing the jobs that were created at companies restructured on Bain’s watch. Dems are emphasizing the layoffs at companies restructured on Bain’s watch — and even more important, the massive profits Bain made in the process. Newt Gingrich waded into this debate when he slammed Romney for making big bucks off of mass layoffs engineered by Bain. The outpouring of conservative rage in response to Newt was another sign of just how high the stakes are in the battle to define Romney’s Bain years.

Today’s Post has a good article on Romney’s Bain tenure, noting that on Bain’s watch, at least five companies filed for bankruptcy, ensuring layoffs even as profits mounted. The Post concludes: “Bain arguably drove some companies to the ground by taking on more debt to give investors dividends earlier.”

Meanwhile, in a sign that Dems recognize they need to put their stamp on Romney’s Bain years before he successfully defines himself as a job creator, the labor-backed Americans United for Change is up with a new Web video that features former imagined colleagues of Romney at Bain confiding that his job — which led to mass layoffs at restructured companies — was merely to “make money.”

The battle to define the meaning of Romney’s Bain years will be fierce — and will assume increasing importance as the campaign continues.

* Have Democrats officially dropped the millionaire surtax? The reporting is conflicted on this question. CNN tells us Dems have decided to drop it. But the Post reports that Dems are still “weighing” whether to drop it.

It seems all but certain that Dems will end up floating a compromise idea to pay for the payroll tax cut extension by other means, perhaps as early as today. Expect Dems to argue that by making a stand on the surtax, they have already succeeded in persuading the public that Republicans prioritize the rich over the middle class, and that they now have no choice but to give ground on this point, because the consequences of failing to extent the tax cut would be too dire for ordinary Americans and the economy.

* GOP works to outmaneuver Dems in payroll tax cut endgame: What to watch today: How Dems handle the GOP’s latest move. Republicans want to pass a measure funding the government, so they can decamp for the holiday, leaving Senate Dems with an unpleasant choice: Either pass the House GOP bill extending the payroll tax cut, or let it expire.

* EMILY’s List putting its stamp on the GOP primary: EMILY’s List, the national pro-choice group, tells me it will be launching a new effort, timed to tonight’s debate, to spotlight the GOP candidates’ rhetoric and policies in terms of what they would mean for women’s rights. The idea is to get an early start driving home the stakes of the election to female voters, who will be a key swing demographic next year. Spokesperson Jess McIntosh, explains:

”Women are watching the primary and its endless debates, and they’re seeing a field that seems to be trying to outdo each other turning back the clock on women’s rights and opportunities. In order to better communicate with the women watching — and judging — these guys, EMILY’s List is announcing the start of an ongoing effort to define the debates. Tonight is the first “Achievement in Awful” Awards given out in three categories: policy, rhetoric, and pandering. We wish the contestants the very best of luck.”

* Newt Gingrich hits back at Romney attacks: Gingrich’s new ad in Iowa seems very effective: He laments the new round of attacks on him without even naming Romney, an effort to maintain frontrunner status while implicitly casting Romney as desperate.

Also note Gingrich’s claim that “11 million jobs” were created after he balanced the budget as Speaker in the 1990s — props to the Clinton economy!

* Can Gingrich pull it off in Iowa? Gingrich still hasn’t put the operation in place he needs to win the state, but he seems to be confident in a win anyway, the latest test of his belief that in this new media era, the old rules of presidential campaigns no longer apply.

* Newt poised for victory: Nate Silver weighs in with his first forecast, putting Gingrich’s odds of victory at around 50 percent, with Romney’s way down at 10 percent, with the key caveat that the race remains wide open.

* Mitt Romney, bleeding heart liberal: The Obama-allied group American Bridge has launched a new parody version of Romney’s 1994 Senate campaign Web site detailing all of his progressive views on abortion and gay rights.

Of particular interest: Romney supported don’t ask don’t tell as a means to accomplish the ultimate goal of allowing gay service-members to serve “openly and honestly.”

* Paul Ryan unveils yet another Medicare plan: Ryan and Senator Ron Wyden will release a new plan today that would offer partial privatization as a choice while preserving the option for retirees to avail themselves of traditional government-run Medicare. Will conservatives view this as a massive cave?

* And will Holder use full force of law on voting rights? A good New York Times editorial gives props to Eric Holder for aggressively calling out the bogus “voter fraud” justification for the national GOP effort to restrict voting.

But the Times raises an important caveat: It still remains to be seen whether the Attorney General will avail himself of all the legal tools at his disposal to crack down on these laws. Definitely something to keep an eye on.

What else is happening?