9:37 PM: I’m curious to see how Romney does when actually challenged on the US auto industry.

9:43 PM: “Time will tell.” “Probably what I’ll do.” Those were Romney’s key lines on taxes. You’ll see a lot of follow ups trying to get him to nail that down to a real commitment.

9:51 PM: Ron Paul: MLK is with me on the drug war and the wars abroad. So even with the newsletters that’s still 2 out of three and that ain’t bad.

9:54 PM: Newt is raucous and shameless as usual. But this is the kind of performance that helped him rocket to the top of the polls.

Running updates on every turn of tonight’s debate at TPMLiveWire.

9:24 PM: This primary race is pretty much over — if we’re talking about any serious chance of Mitt Romney not being the nominee. But there are a lot Republicans watching that last exchange who had some real heartburn. When at all seriously challenged, Romney quickly loses his cool. That’s a problem if you’re in a race with serious opposition — which Romney really hasn’t been.

9:01 PM: And here we go. Any real way Romney can muff this at this point? I doubt. What’s different now is that I really wonder whether Gingrich, Perry, Santorum even have the oooomph left in them to make a real fight of it tonight.

9:04 PM: Mitt’s giving Newt that, “Dude, I’ve so smoked you look.” … Actually not a bad answer from Gingrich … The subtext is pretty clear here: Newt, what the F were you thinking?

9:07 PM: Pretty clear at this point that Fox has fallen into line on this one. Baier didn’t press Romney on the tax issue, which surprises me.

9:14 PM: Romney is amazingly cocky in this debate. Thing is though, why not? At this point there’s just no one up there who can really challenge him and in the national numbers the big move to Romney has started.

9:17 PM: I’m not sure I’ve seen something like this before. The whole subtext of the debate basically is challenging everybody to shut up and stop attacking Romney.

9:21 PM: Man, if only Santorum weren’t a hopeless candidate, this sort of good debating might actually make him a contender.

Tonight’s South Carolina debate is at 9 PM. Here’s what to watch for. We will of course be here covering it live.

TPM’s video-masher extraordinaire Michael Lester brings us a killer compilation of Jon Huntsman’s greatest moments, right up to today’s endorsement of Mitt Romney.

Meanwhile, the Dems have a sharp little video reminding everyone that Huntsman was until recently one of the toughest critics of the man he’s just endorsed.

Elizabeth Warren and Scott Brown could be on the verge of testing out how far you can batter back third-party ads in this post-Citizens United era.

An increasingly central theme of Obama’s reelection bid is that he’s donning the mantle of Teddy Roosevelt and taking a stand against the growing unfairness of income inequality. But is there all that much a modern President can actually do to tackle this trend?

Sahil Kapur on why House Republicans oppose the Democrats’ easy solution to the “Doc Fix” problem.

A month ago I pointed to some patterns which have shown up in the 2012 primary cycle which suggest to me that the digital news revolution (which is really a nationalization of news) may be changing the role early primary and caucus states have played in US politics for forty-plus years.

Put simply, the old idea was that these smallish states were largely self-contained political news worlds where a kind of intensive, organization-heavy politicking ruled the day. Because of this, each was its own little contest, in which a different set of candidates might catch fire. But multi-platform, 24/7 political news and chatter is now so pervasive that these different battles don’t look that distinct.

It doesn’t speak directly to this issue. But Mitt Romney looks to be doing pretty well in South Carolina. He has a solid lead. But political hands in the state tell our Evan McMorris-Santoro that Romney’s managing to do it with very little of the retail-style campaigning which has been so critical to past winners. We’ll have to see how it pans out. But I think this is part of the same trend.