Is Barack Obama pulling away from Mitt Romney? Two polls that came out yesterday suggest the answer could be yes. According to CNN, Obama has improved from a narrow 49 percent to 46 percent lead in July to a more convincing 52 percent to 45 percent. A Fox News poll has Obama lead 49 percent to 40 percent.

You don’t have to take these polls entirely at face value — there have been complaints about party ID sampling — to notice a trend: Obama’s gains seem almost entirely driven by voters taking a more negative view of Romney. At first it looked like Obama had thrown his best punch without any effect. The numbers seem to be shifiting amidst the barrage of ads.

Team Obama is spending money early to define Romney negatively before the American people develop an independent sense of who he is or begin to sympathize with Romney’s business record in a bad economy. Romney is continuing to raise money and mostly holding his fire, betting that his own ads will have a greater impact in the fall when everyone is paying attention.

Matthew Continetti reminds us that George W. Bush decided to go negative early and the last Massachusetts liberal to run for president made the same bet Romney did. We all remember how that turned out. Obama’s ad campaign is especially aimed at decreasing turnout by working-class whites, who would otherwise be poised to vote against him by a landslide margin.

The big difference between now and 2004: Obama’s numbers are worse than Bush’s and the objective conditions of the country are much worse. Bush still had an approval rating hovering around 50 percent and was at 53 percent approval among those who turned out on election day. Romney still has a lot to work with. But he’ll have to define himself positively as well as point out that the current administration has failed.