The question in the Florida Republican primary tonight is not whether Mitt Romney wins, but by how much. "What they need," New York's John Heilmann writes, "is a result that screams that they have decapitated Gingrich, and then played soccer with his severed head." That means double digits. Gingrich set expectations for himself -- low but not decapitation-low -- Tuesday, telling Fox, "If you watch tonight, my prediction is the conservative vote will be dramatically bigger than Governor Romney’s....So we’ve got to find a way to consolidate conservatives, and I’m clearly the front-runner among conservatives." Polls close at 7 p.m., but because part of Florida is in the Central Time Zone, the networks won't call the race before 8 p.m. Eastern time. We'll be liveblogging the results starting at about 7 p.m.

Updates:

9:43p.m.: Romney has 46.4 percent of the vote to Gingrich's 31.9 percent, with 98 percent of precincts reporting. The conventional wisdom said Romney had to win by big double digits, and he did. Gingrich said his own task was to show that the combined conservative vote was bigger than Romney's, and by a hair, it isn't. Santorum got 13.3 percent, meaning the conservative vote totaled 45.2 percent, less than Romney's vote. (That's unless you count Ron Paul's 7 percent, which Ron Paul fans probably wouldn't appreciate.) But Gingrich vowed to fight on anyway.

Nevada's caucuses are Saturday.

9:40p.m.: In a blue v-neck sweater, Ron Paul tells an adoring crowd -- he says thousands are there, though Fox anchors are skeptical -- that he'll keep fighting for liberty. 

(Photo via Associated Press.)

9:26p.m.: Gingrich's speech gets the best reviews on Fox. Karl Rove says he looks like a "robust conservative executive," just like in the '90s.

9:24p.m.: "Newt promises to get rid of czars. Communists got rid of czars. Ergo, Newt is a communist," The New Republic's Jonathan Cohn tweets.

9:19p.m.: A dig at Romney: "I'm not going to try to compete with Obama on singing because I'm not running for entertainer in chief." A joke but no smile:

9:17p.m.: Why doesn't Gingrich smile when people clap for him?

9:12p.m.: Gingrich: "This is The. Most. Important. Election. In. Your. Lifetime."

9:10p.m.: Newt says Florida has done something very important. No, not pick the nominee. The state has made it clear it's a choice between two guys: a conservative candidate and a Massachusetts moderate.

9:08p.m.: There is a slight wave in Callista's hair. A chink in the armor! 

9:07p.m.: "Newt is backstage. Ready to take the podium," Gingrich tweets. He's getting pumped.

9:03p.m.: With 80 percent of precincts reporting, Romney's ahead by 16 percentage points.

8:59p.m.: Rick Santorum, who's getting about 13 percent, congratulates Romney and says his daughter Bella is doing better. Florida taught us, Santorum says, that "Republicans can do better." No one wants a "mudwrestling match where everyone walks away dirty."

8:53p.m.: "Mitt's speech sounds more like a guy accepting nomination than a guy who won his 2nd primary," ABC News' Amy Walter tweets. His speech was gracious toward his opponents and focused on Obama. "Leadership is about taking responsibility, not making excuses… Well Mr. President, you were elected to lead. You chose to follow.  Now it's time for you to get out of the way," Romney said.

"Together we will build an America where hope is a new job with a paycheck, not a faded word on an old bumper sticker," he continued. His America would not reflect "the worst of what Europe has become."

8:50p.m.: On Fox, Sarah Palin says all the negative ads -- especially all that money Romney spent -- hurt Republicans. Romney's $17 million, Palin said, made it hard for Gingrich and Santorum to fight back. "When a bell is run it's hard to unring it… it unfortunately is what keeps good people from running for office." Good people like Sarah Palin?!

8:41p.m.: When Romney gets applause, he always does the same thing: tight "hard truths" smile, look down, look left with same smile and a slight nod. Over and over and over.

8:34p.m.: In his victory speech, Romney promises that a "competitive campaign does not divides us, it prepares us."

8:29p.m.: The Romneys, sans Mitt, greet the crowd:

8:26p.m.: Gingrich rally looking slightly less desolate:

8:25p.m.: Gingrich hasn't given his concession speech, but he's already asking for more money. "46 States to Go! Donate today and help us defeat Obamneycare. 1 million dollar money bomb," he tweets, stealing the line from Tim Pawlenty that the former Minnesota governor wouldn't say in a debate. Pawlenty is backing Romney now.

Note: financial disclosure documents today show the Gingrich campaign is $1 million in debt.

8:22p.m.: Romney spokesman Ryan Williams tweets Romney snacking while watching returns:

8:19p.m.: Happier times at the Romney party:

8:14p.m.: Gingrich's rally site:

(Photo via Reuters.)

8:10p.m.: "Mittworld thinks final margin will be 15-18," Politico's Jonathan Martin tweets.

8:09p.m.: Gingrich won among married women in South Carolina. Not even close in Florida. Romney won 51 percent of women and 41 percent of men, CNN exit polls show. A few other interesting tidbits from the exit polls:

• Romney, despite going so far to the right on immigration some Republicans are getting nervous, won 53 percent of the Latino vote. Gingrich got 30 percent.
• Ron Paul didn't win young people tonight, getting 26 percent of those under 30. Romney got 39 percent of them. (Youngsters were just 6 percent of the electorate though.)
• Romney won all income and education levels. In South Carolina, Gingrich won every subgroup but those making more than $200,000 a year and those with post-grad degrees.
• Gingrich won those calling themselves "very conservative," getting 43 percent of those folks, and he won those who strongly support the Tea Party, getting 46 percent of their votes.
• Gingrich won born-again voters, with 39 percent of their vote.
• Gingrich won people who thought abortion was the most important issue and those who think it should always be illegal. 
• Gingrich won those who think the most important quality in a candidate is being a true conservative (won 45 percent of their vote) and those who said having the right experience is most important (45 percent).

8:04p.m.: Gingrich is the first Republican candidate in history to win South Carolina but lose Florida, Fox reports.

8:00p.m.: Fox News calls Florida for Romney; with 56 percent of precincts reporting, he has 48 percent of the vote to Gingrich's 31 percent.

7:55p.m.: A voter made her way to the polling station in Celebration, Florida to meet Gingrich Tuesday:

(Photo via Associated Press.)

7:46p.m.: Analysis of donors to the superPACs shows that almost all of them got the vast majority of their money from one donor, the Times reports. Only Herman Cain's PAC got money from mostly small donors, with only one person giving more than $5,000. The Paul-backing PAC Endorse Liberty got 98 percent of its money from Peter Thiel, the pro-Huntsman PAC got 97 percent of its money from Huntsman's dad.

7:43p.m.: Gingrich's robocalls claiming Romney denied kosher food to elderly Holocaust survivors did not send packs of Jewish folks to the polls tonight. Jewish turnout is low, the Times reports, with only 1 percent of tonight's Republican voters saying they're Jewish. In 2008's Republican primary, 3 percent were Jewish.

7:40p.m.: With 21 percent of votes in, Romney's ahead 48.9 percent to Gingrich's 30.3 percent.

7:32p.m.: Latino voters are 15 percent of the Republican electorate this year, the Times reports. They were just 7 percent in 2000. 

7:31p.m.: More than half of Florida voters say Romney is the most electable candidate, exit polls say, but only a third say Romney is the most empathetic candidate, The New York Times' Allison Kopicki reports.

7:26p.m.: Talking Points Memo's Evan McMorris-Santoro posts this photo from the site of Gingrich's likely conecession speech tonight:

No need to use up all those classics from the Gingrich photo archive, guys. He's staying in it for a while.

7:23p.m.: Noted Romney fan the Drudge Report now forecasts these results:

7:21p.m.: Fox reports that exit polls show half of senior citizens voted for Romney. Old folks were once Gingrich's base.

7:15p.m: Tagg Romney posts this photo of the Romney war room:

Not sure what they'll have to war about, given the expected results.

6:15p.m.: In his traditional poll returns early leak, Matt Drudge is reporting that Romney is beating Gingrich in Florida, 46% to 32%. As Drudge says, "Developing..."

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Elspeth Reeve