I was once shooting the breeze with a Democratic senator I knew fairly well. This was a few years ago, back when the toxic atmosphere wasn’t quite as hideous as it would become. Just on a personal level, I asked: Who on the other side is surprisingly nice, and who’s just a real prick? I don’t remember the surprisingly nice answers, but on the S.O.B. factor the senator’s response was immediate: David Vitter.

He’s a nasty piece of work, the junior senator from Louisiana. He doesn’t seem to like anybody. He loathes senior senator Mary Landrieu, he detests Governor Bobby Jindal, he despises the media. They all pretty much hate him back. And yet, by merely announcing, he immediately became the odds-on favorite to win the governor’s race in 2015. Why?

The announcement may seem surprising to those of us outside the state, but “this was the worst-kept secret in Louisiana,” a political operative with knowledge of the state told me Monday. Vitter has been holding a series of town-hall meetings and tele-town-hall meetings, signaling the obvious intention.

I’ll get to race handicapping in a few paragraphs, but first let’s deal with the only thing most people know about David Vitter (who has not, by the way, distinguished himself in the Senate in any way). I’ve always wondered: How in the world did he survive that hooker business? Not only did he admit he was a client of Deborah Jeane Palfrey’s escort service. She then went and hanged herself. Not over him personally. Over the whole mess, and staring at serious jail time. But still. Extramarital relations are one thing, with a staffer or a woman of accomplishment; politicians almost always slog their way through that. But here we had the guy calling on hookers, and the dead body of the madam. And Vitter skated through it and sailed to reelection two years later. How?

“He hid for a year and a half,” says my operative. At first, when his name was revealed by Hustler in connection to the case, Vitter acknowledged it. He said he’d asked for and received his wife’s and (somewhat presumptuously) God’s forgiveness. After that he would say no more—“out of respect for my family.” Nice touch.

By the time 2010 came around, Palfrey was less important to the state’s voters than the fact that Charlie Melancon, the Democrat who challenged Vitter, had “voted with Barack Obama 98 percent of the time” in Congress. That’s all Vitter said. That, and the forgiveness thing, and the “fact” that illegal immigrations were cutting holes through chain-link fences and being welcomed by bleeding-heart Melanconistas with a brass band and a waiting limousine, as this really vile and racist TV ad of his had it. Vile and racist works down there, so what had seemed at first like a close-ish race became a 19-point whupping.

Ever since, Vitter has been fine, with his approval rating up in the high 50s. I guess all it takes to do that is to be right wing and anti-Obama. And so, he’s the favorite to be the state’s next governor.

But that could change. The declared field so far is no great shakes—the Republican lieutenant governor and a Democratic state representative. Not even any members of Congress yet. But here are a couple of developments to keep an eye on. First, New Orleans Mayor Mitch Landrieu, a Democrat, faces reelection on Feb. 1. He’s expected to roll to an easy win. “If it’s a landslide, he’ll have to consider the governor’s race,” says the operative. Second, there’s Mary Landrieu’s (they’re brother and sister) reelection this fall. That’s expected to be very close. If she loses and is out of a job, might she give it a shot? She and Vitter have the reputation of disliking each other more, maybe a lot more, than any other state’s two U.S. senators. Landrieu v. Vitter for governor would be awesome.

But even if the field doesn’t get a lot stronger, Louisiana politics blogger Robert Mann still thinks Vitter might have a harder time than he did in 2010. It’s not always great to be the front-runner this far out, because everyone below you is attacking you. And, Mann notes, Vitter’s not going to be able to make this race about Obama, who’ll be on the way out in 2015.

There’s an interesting Vitter-Jindal subplot going on here, which is nicely detailed by Marin Cogan at The New Republic, and the issue of whom Jindal might endorse is an interesting one. Though he’s unpopular overall in the state, he’s still in decent shape among the state’s Republicans, so his word might carry some weight. But he’ll be off running for president in 2015 (yes, he still apparently thinks he can do this!).

So Vitter is all in. And even if he somehow loses the governor’s race, it’s no real skin off his nose—he’d remain a senator, because that seat isn’t up until 2016. And running for reelection then, he can just run ads with Hillary Clinton welcoming swarthy illegals with open arms. Easy peasy. One way or another, we’re stuck with this guy for a while.