It's the kind of dumb statement that candidates make when they get tired. It's the kind of lame utterance that campaigns dread when it's their candidate who makes it, and exploit for all its worth when their opponent gives them a gift. All of the above happened on Friday, when a crowd at a rally for Barack Obama booed the mention of Mitt Romney. "No, no, no.  Don't boo, vote," Obama responded, quieting the crowd. "Voting's the best revenge."

It didn't take Mitt Romney long to work that into his closing message of the campaign this weekend. "Did you see what President Obama said today?" Romney asked a crowd later that evening, setting up the slam dunk. "He asked his supporters to vote for 'revenge.' For 'revenge.' Instead, I ask the American people to vote for love of country."  

Within 24 hours, the Romney campaign had a television ad featuring the contrasting final messages playing in swing states. The Obama campaign didn't have much room for rebuttal except to attack Romney for highlighting Obama's remark. That didn't have much effect, except to confuse Chris Matthews of MSNBC into thinking that it was Romney who called for revenge — and promptly declaring the argument racist.

Obama's 'revenge' remarks are at least as revealing about this campaign as were Romney's 47 percent statements.

Sure, it would be easy to dismiss this as a minor stumble. Candidates make verbal gaffes in the course of a campaign. It wasn't that long ago, for instance, that a video of Romney making dismissive comments about the 47 percent surfaced, and the Obama campaign exploited that for weeks. Obama even brought up the 47 percent during the final debate in his closing comments. Romney eventually walked those remarks back, but some credited Obama's polling gains in September to the damage done by the video.

However, Obama's "revenge" remarks are at least as revealing about this campaign, and of Obama's approach to both this election and to public policy, as were Romney's 47 percent statements. The president, in both his campaign and his administration, has gone fully populist, attempting to divide the country along class lines as a distraction from his record in his term in office. In fact, the best description of Obama's politics since September 2011 is "the politics of revenge."

It started with the collapse in summer 2011 of a "grand bargain" that Obama wanted as part of a debt-ceiling deal. As Bob Woodward's book later made clear, Obama ended up angering both Democrats and Republicans, and blew a deal with John Boehner by attempting to up the ante on tax hikes at the last minute. Obama's budget director, Jack Lew, finally proposed that Congress punt the ball a little longer by passing a debt limit to stave off the acute crisis in exchange for "sequestration" — automatic cuts that would take place in the absence of bipartisan budget reform. Boehner and Harry Reid accepted Lew's framework, but largely cut Obama out of the loop otherwise.

Stung by the outcome of the deal and the largely accurate perception that he'd fumbled the negotiations, Obama responded by demanding tax hikes on the wealthy as part of any new deal. Nevermind that his threshold of $250,000 annual income would include small-business owners. Nevermind that the revenue of such a tax — around $80 billion per year — would hardly put a dent in Obama's trillion-dollar deficits. Obama's rhetoric soon focused on the 1 percent, and income inequality became Obama's principal focus while most Americans worried about jobs.

Romney's nomination gave Obama the perfect opportunity to vent his populist spleen. Here was almost the personification of income inequality and privilege — the epitome of all Obama had demonized during the previous several months. Accordingly, the Obama campaign quickly went negative against Romney, running more than $100 million in ads that focused mostly on Romney's wealth, his business decisions at Bain Capital, and his reluctance to disclose the 20 years of tax returns that Team Obama wanted. Deputy communications director Stephanie Cutter even alleged that Romney might be hiding a felony, a charge that Senate Majority Leader Harry Reid repeated numerous times — with zero proof. Romney's remarks about the 47 percent gave this strategy one last big boost in the final weeks of the campaign.

Even on a personal level, the hostility seemed palpable. During the first debate, Obama looked and sounded put off by having to even address Romney's criticisms on stage, and offered the same attack lines as his summer campaign. In the next two debates, Obama glared and glowered at Romney, and spoke to him with scorn dripping from every word. Only after the last debate did Obama finally get around to releasing anything resembling an argument for a second term as president, offering voters a 20-page pamphlet that consisted almost entirely of recycled pledges from the 2008 campaign. Perhaps Obama was caught by surprise that the majority of voters didn't view Romney with the same level of disdain, and that Obama needed to make an argument for their vote.

For Obama, this entire campaign has felt like revenge against Romney, and against the kind of people Obama thinks Romney represents.  Obama could have spent the last several months talking about his own record and his plans to change direction from our current economic stagnation that has kept the level of employment in the population at or near 30-year lows. Instead, Obama approached this election as a personal mission of revenge, and left the door open for Romney to present the only vision of change for the future in this campaign. Romney defined his campaign as an expression of love rather than revenge. So what Obama said on Friday was no gaffe. It's just the obvious takeaway from a relentlessly empty and negative campaign.