The race is on to define Mitt Romney. President Obama’s vulnerabilities as an incumbent this year foreshadow a nasty, mudslinging campaign this fall, from both candidates. The president, his advisers no doubt believe, must define Romney now before independents come to think of him as a preferable alternative. And the Romney team, facing a personally well-liked incumbent in the White House, will have to tear down his tenure in office.

The Obama campaign [not to mention assorted super pacs] will have all the money it needs, so early advertising in swing states is already upon us. Last week’s Washington Post article neatly sums up the approach the Obama team is taking with regard to interpreting who Mitt Romney is: “He’s a bully. He was a bully in high school, he was a bully at Bain Capital, and he’s a bully now. He’s wrong for America.”

They will spend millions of dollars driving home that message. It might work. But here are the risks: The Romney campaign will likely have an answer, or their version of the truth, for every anti-Bain spot that runs. Many voters will find it old news that was already debated in the GOP primaries. But worst of all, independent voters in swing states this summer and fall could decide that “hey, you know what? In this economy, someone like Romney is what we need – someone tough, who knows how to make the country turn a profit, and who won’t apologize for it.”

Actually, the President has been on the campaign offensive for weeks now. One could look at his trip to Afghanistan as a Nixonesque bid to claim the title of world leader and peacemaker. The gay marriage issue is being used, and will be used, to compare and contrast the “moral compass” of the two candidates. And the Bain Capital ads will be ubiquitous throughout the rest of the year. In fact, much of the fall campaign will likely be a contest to define the meaning of Romney’s accomplishments at Bain – much like the 1992 campaign was at least partly a debate about the economy and culture of the 1980s.

The polls are close. We’re in store for a good old-fashioned, head banging, months-long scrum. Who will bring a knife to the gunfight?