For the first time, the Gallup daily tracking poll shows the president’s approval ratings dipping below 40 percent. Is it time for the Obama administration to start panicking?

Well, yes and no. The Obama administration should be worried, but not because of the Gallup numbers. Ronald Reagan started the third year of his presidency with his approval rating at 35 percent, while George H.W. Bush, who went on to lose reelection a year later, had approval ratings in the 50s in August of 1991.

What should worry the Obama administration is the reason Reagan won and Bush lost — economic growth. Strong economic growth in the later stages of the first Reagan administration resulted in his winning reelection by a landslide—while a faltering economy ensured the elder Bush would lose reelection to Bill Clinton.

When I spoke to political scientists and economists about Obama’s chances for reelection in 2012, they said that at the very least, GDP growth would have to average about 2 percent per quarter for Obama to be reelected based on date from prior elections. Growth in the first quarter of 2011, meanwhile, was a paltry .4 percent.

So there’s little point in wringing one’s hands over daily approval ratings. It’s still the economy, stupid, and what will likely determine the outcome in 2012 is not how the president’s approval ratings look today but what the economy looks like over the course of the next year or so.