Every political debate seems to promise angry clashes, but with Newt Gingrich attacking Mitt Romney and Romney attacking right back, the NBC News debate in Tampa at 9 p.m. is expected to be particularly contentious. Last fall, a little fight over immigration last fall got Romney mad enough to grab Rick Perry's shoulder, so now that Newt Gingrich is not only attacking Romney but beating him in polls, we can hope at minimum for a little choking Homer-on-Bart-style. NBC will not install a metal cage, but we expect Romney to attack Gingrich on his lobbying career and his conservative credentials. Gingrich will attack Romney on his the taxes he pays and conservative credentials. Rick Santorum will attack both of them on their conservative cred -- especially on health care -- as he tries to make his case as the reasonable conservative alternative. Ron Paul will declare all three of them foes of liberty. We'll start liveblogging at about 8p.m.

Updates:

11:25p.m.: What we learned: Mitt Romney mentioned for the second time in a debate that he forced Ted Kennedy to take out a second mortgage on his house when he ran against him for Senate in 1994. Two mentions makes it seem like a genuine emotion. Note: never play sports with Mitt Romney. He will probably kick you in the shins and steal the ball. And Romney taught us a new word tonight: "self-deportation." His attacks on Gingrich demonstrated that Newt's not that great when he has to spend a lot of time explaining how he worked as a historian for Freddie Mac -- sometimes "as a historian of Washington," he allowed. George W. Bush finally got a reference in the debates -- for his low approval ratings and how that sunk Santorum in his 2006 reelection race. For Ron Paul, a big suit means bigger shrugs. He didn't like flirting with a third-party run at first, but it's growing on him.

11:00p.m.How to decide who won tonight? A lot of people (on Twitter, and no, none of them were pornbots) are saying Romney did well by riling up Gingrich. But tallying up the most memorable lines of the night, it's harder to justify the argument that Romney won.

Best lines:

  • "When push came to shove they got pushed" -- Santorum, on Romney and Gingrich. Also: "They rejected conservatism when it was hard to stand."
  • Williams: "If Gingrich is the nominee, will you go your own way?" Paul: "Well I've done a lot of that in my lifetime."
  • "I don't ask people to be for me... I ask them to be with me." -- Gingrich's closing argument, on how undoing everything President Obama has done will be hard and will require bringing the country together.

Worst lines:

  • “What a great thrill that was. I didn't beat him, but he had to take a mortgage out on his house to defeat me." -- Romney on nearly bankrupting Ted Kennedy when he ran for his Senate seat in 1994.
  • "I pay all the taxes owed.  And not a penny more. I don't think we want someone running for president who pays more taxes than he owes." -- Romney on what people will find when his tax returns are released tomorrow.
  • "Well, the answer is self-deportation, which is people decide that they can do better by going home because they can’t find work here because they don’t have legal documentation to allow them to work here." -- Romney on how to get all the illegal immigrants to go home without forcibly deporting them.
  •  "First of all, he may have been a good financier, but he's a terrible historian." -- Gingrich on Romney, and imaging a terrible insult in his world is a terrible insult to the rest of us.
  • "..." -- Gingrich's long silence before he answered Romney's charges that he was peddling influence after he left Congress.

10:37p.m.: Ron Paul makes the case that when it comes to governing, there's not a dimes worth of difference between the parties. "Our rhetoric is still good but when we get into office," he begins. For every Democratic Dodd-Frank bill, there is the Republican Sarbannes-Oxley. This sounds like a general election message. If you're running as an independent.

10:22p.m.: It's offensive that Gingrich didn't get the first shot at the space question. That is his issue! 

He says he sees us "going back to the moon permanently." He envisions "very romantic and exciting futures." This is the Newt we know.

10:20p.m.: Santorum gets a question on Terry Schiavo. He's oddly dispassionate on an issue you would think would be important to him, with his campaign focused on social conservatism.

10:16p.m.: Pretty disappointed that so far Romney has not made any physical contact with Gingrich, much less one that would result in a little bubble over his head saying "BONK."

10:13p.m.: How can Romney send all the illegal immigrants home if he doesn't send them home? They will engage in "self-deportation," naturally. This seems like a moment when Romney's corporate background is showing.

10:06p.m.: Paul's ill-fitting suits make it much more cartoonish when he shrugs.

10:00p.m.: It's hard to know what to say when the candidates are so excited about war with Iran. Santorum, the most enthusiastic, says it would be irresponsible not to take action to stop Iran from getting a nuke. But he ignores the point of Williams' question -- how would you define the targets? How long would it last? What would we do afterward?

9:55p.m.: Gingrich and Romney fighting over Gingrich's lucrative consulting career:

9:52p.m.: "Governor Romney, How do you win the war in Afghanistan without talking to the Taliban?" "By beating them." Oh, beating them! Why didn't we think of that 10 years ago?

9:48p.m.: Gingrich finally gets his applause by saying Fidel Castro will go to hell. "I don’t think Fidel is going to meet maker. He’s going to the other place."

9:45p.m.: Newt is better when he can fight someone who can't fight back -- the moderators -- and when he's got people cheering him on. We can't hear rowdy audience members this time (nor can we see them dressed like George Washington). The conventional wisdom (on Twitter) seems to be that by attacking Gingrich on influence peddling on health care when he was a "consultant." That forced Gingrich to go into a long explanation of his record as a private citizen and then passionately defend Medicare Part D, which pays for prescription drugs, and government-sponsored enterprises, like some utilities and yes, Freddie Mac. But maybe Gingrich was making the case that he actually believes in things. Romney is not so convincing on that score.

9:40p.m.BuzzFeed posts Romney's careful answer about his taxes:

9:34p.m.: Gingrich listens to Romney attack him as a lobbyist. Can you spot the moment when he decides he's got this?

I'd say photo No. 4, but you could make the case for No. 3.

9:23p.m.: It's fun to watch Romney talk about his taxes.

9:21p.m.: Yes! A hint of what might be in Romney's taxes: "I pay all the taxes owed.  And not a penny more. I don't think we want someone running for president who pays more taxes than he owes."

9:17p.m: Paul again asked whether he's running as a third-party candidate. "If Gingrich is the nominee, will you go your own way?" Williams asks. "Well I've done a lot of that in my lifetime," Paul says.

9:14p.m.: Finally in these debates, we get a reference to George W. Bush! When asked whether he can win -- given he was destroyed in 2006 -- Santorum says, hey, lots of other guys lost that year! Plus, Santorum says, he was working with the president on Iraq and Social Security, and he had a really low approval rating.

9:10p.m.: "First of all, he may have been a good financier, but he's a terrible historian." That's a harsh put-down in Newt-world. What about in everyone else's world?

9:08p.m.: Romney looks unhappy from minute one:

9:05p.m.: One of the questions before the debate was whether Gingrich would attack the media as he has so successfully in earlier debates. He does take on moderator Brian Williams, but more subtly tonight, saying that when he was speaker he passed four consecutive balanced budgets. "The only time in your lifetime, Brian, that we've had four consecutive balanced budgets."

8:53p.m.: Gallup's daily tracking poll finds Gingrich now nearly tied with Romney. A week ago, Romney was ahead, with 37 percent of voters' support to Gingrich's 14 percent. Two new robo-polls find Gingrich ahead of Romney in Florida by more than 8 percentage points. Last week, pollsters in the state were predicting Romney could win with more than 50 percent of the vote.

8:43p.m.: "My channel guide says Fear Factor is on NBC at 9, so I guess they decided to name this debate," Balloon Juice's John Cole tweets.

8:33p.m.: Miriam Adelson will give $5 million to Winning Our Future, the pro-Gingrich superPAC (not to be confused with Restore Our Future, the pro-Romney superPAC), The New York Times' Nicholas Confessore reports. She's the wife of Sheldon Adelson, the casino magnate who gave Gingrich's PAC $5 million earlier this year, which allowed the group to air a whole bunch of ads attacking Romney for his business career. 

Florida is a much more expensive state to air ads in because it's big and has pleasant weather, so tons of people actually want to live there, unlike certain other early voting states. It has some of the biggest media markets in the U.S., and there was some speculation about whether Gingrich would be able to compete with the well-financed Romney's airtime. This donation will help.

8:22p.m.: Certain liveblogs engage in debate "drinking games," in which participants take a shot every time the candidate says something like "anchor baby" or "freedom." The Atlantic Wire does not sanction these games. That is because because if you ever actually play this game with friends -- as opposed to pretending to while you blog alone in your sweatpants -- everyone starts talking and you can't hear the candidates say ridiculous things. And on a deeper level, these "games" try to make debates "fun" for people who would not normally like them. This is impossible. Either you are a normal person, or you are a sicko who enjoys watching our elected officials make the case against democracy on live TV. Normal cannot be converted to sicko with a few shots of Jim Beam.

8:15p.m.: Just before the last debate, Gingrich posted his tax return from last year online. Tonight, he's posted his 2006 contract with Freddie Mac. The Gingrich Group's press release says it shows he did no lobbying.