OFF TO A SLOW START…. To a certain extent, the 2012 presidential race started a few hours after the 2008 race ended, but in a more literal sense, the next cycle is off to a surprisingly slow start.

We’re about a year away from the first nominating contests — Iowa caucuses, New Hampshire primary — and the field of Republican candidates, expected to be massive, has exactly zero candidates. At this point in the last cycle, 14 presidential candidates were already in the race.

Granted, the 2008 cycle was considerably different. It was, after all, the first presidential race in more than a half-century in which neither an incumbent president nor incumbent vice president ran. The wide-open qualities attracted a large field on both sides.

But given modern standards, we’ve come to expect fairly long presidential campaigns. Even at this point in 2003, with George W. Bush riding fairly high in the polls, all six of the major Democratic candidates — Kerry, Edwards, Dean, Clark, Gephardt, and Lieberman — had at least launched exploratory committees, if not formally declared.

This year, we can say with some certainty that there will be a sizable GOP field, but the fact remains that not one has begun campaigning in earnest. How come? Mark Halperin recently offered an explanation.

No one is in a hurry to jump in because there isn’t a strong-armed front runner threatening to squash the rest of the pack the way George W. Bush did in 2000. None of the hopefuls want the scrutiny or expense that goes with becoming an official candidate. And no one but the most fervent activists and hyperpolitical reporters is itching to get another election under way.

There’s probably something to this. I suppose Romney is the presumptive frontrunner, but he doesn’t exactly scare anyone — in either party — or give the impression that he’s a powerful force in American politics, so likely GOP rivals have less of an incentive to get in the game quickly and establish themselves as credible challengers/alternatives.

But there’s one thing Halperin didn’t mention, which is worth keeping in mind. As Kevin Drum noted today:

And while we’re on the subject of why not a single Republican has announced a presidential candidacy yet … isn’t the answer obvious? It’s because they all know Barack Obama is as good as a shoo-in in 2012. Unless something cataclysmic happens, the only reason for any Republican to run is either as a vanity candidate or to get practice for 2016.

I’m not nearly as certain as Kevin about President Obama’s chances, but I’d still love to know just how much this is influencing Republicans’ thinking.

Publicly, they’re filled with bravado — Obama misread the public, Obama’s agenda has been rejected, Obama’s outside the mainstream, yada yada yada. But behind closed doors, I have to wonder if some of these folks pause to appreciate the fact that they’ve thrown the kitchen sink at the president, and despite all kinds of problems, Obama’s approval rating is still 50% — and climbing.

Does that give some would-be presidential candidates pause? I’d be surprised if it didn’t.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.