By MICHAEL FALCONE ( @michaelpfalcone ), AMY WALTER ( @amyewalter ) and SHUSHANNAH WALSHE ( @shushwalshe )

DES MOINES - Good morning from Iowa!

In the midst of an election season when debates matter, this night could be a turning point in the race for the Republican nomination.

With Newt Gingrich and Mitt Romney locked in a pitched battle at the top of the GOP pack and a cadre of other candidates looking to steal their thunder, the stakes could not be higher for tonight's ABC News, Yahoo News, WOI-TV, Des Moines Register, Iowa Republican Party debate, which begins at 9 p.m. Eastern/8 p.m. Central.

The debate, which will be moderated by ABC's Diane Sawyer and George Stephanopoulos, takes place on the campus of Drake University in Des Moines - in a state where voters will gather less than a month from today to kick off the process of selecting the Republican nominee.

To watch, tune into any ABC television station across the country or log on for a live-stream on ABCNews.com, Yahoo.com, MyABC5.com, and DesMoinesRegister.com. And look for special coverage and analysis tomorrow on "This Week" with Christiane Amanpour.

As ABC's Matthew Jaffe notes in his preview of tonight's showdown, "the prime-time debate comes as the GOP race has started to reach a boiling point." With Gingrich surging, Romney and his allies have launched scathing attacks from all sides. http://abcn.ws/v5GkaN

"The flurry of attacks should come as no surprise to Gingrich: It's what happens when you're on top. Every poll released this week seemed to bring better and better news for Gingrich," Jaffe writes. "It's all leading up to a fascinating - and potentially explosive debate."

In an exclusive interview with ABC's David Muir in Iowa yesterday, Romney declared that Gingrich would be the easier candidate for President Obama to beat in the general election - "no question in my mind," Romney said.

And in a preview of things to come, Romney noted, "I'd expect Newt Gingrich and I will have some differences and we'll be able to discuss those," tonight.

For his part, the former House Speaker has been less willing to go after the former Massachusetts governor, but as ABC's Jake Tapper points out, that may not last long. Case-in-point: In an interview yesterday, Gingrich accused Romney of "running to the left of Teddy Kennedy in Massachusetts in 1994." http://abcn.ws/tPhEcH

"He wasn't for the Reagan-Bush policies," Gingrich said, "he was independent."

With Gingrich and Romney primed for a fight and Rick Perry, Michele Bachmann, Ron Paul, Rick Santorum ready to engage their rivals, buckle up for debate night in Des Moines.

TWEETERS TAKE NOTE: TONIGHT'S OFFICIAL HASHTAG: #IowaDebate

WHAT WILL GINGRICH DO? ABC News Political Director Amy Walter and Yahoo News Washington bureau chief David Chalian tackle the question: "What should we expect to see from the newest frontrunner, Newt Gingrich?"

Chalian : First and foremost, I expect to see an inherent tension within Gingrich on stage. He has had such great success trying to stay above the fray and has made his pledge to promise only positive campaigning. It seems to me that will be in direct conflict with being the frontrunner and the likely target of nearly everyone else on that stage. Watching how he navigates through that tension will be fascinating, don't you think?

Walter : Absolutely. And, then there's the fact that Gingrich has, in the past, been his own worst enemy. Staying on message has never been his strong suit. But, his opponents have to be careful too. As we've seen in past debates, the candidate who stays above the fray - whether that's Cain or Gingrich-has benefitted. So, I'm just as fascinated to see what Romney does. Does he try to let the other candidates take their shots at Newt or will he have to do it himself?

AMY WALTER'S BOTTOM LINE: "In the end, the candidate who 'wins' the debate will be the one who is able to not only engage and energize the Republican base, but one who also looks like he/she is able to translate that success beyond the primary season and into the general election. Today, polls show that Gingrich is that guy. But, will he still be that guy on Sunday morning?" More from the political brain trust of Walter and Chalian in their debate night preview: http://yhoo.it/uZ1t0t

ABC's Jake Tapper rounds up yesterday's action on the presidential campaign trail in Iowa. WATCH: http://abcn.ws/uIq8aT

YAHOO WANTS TO HEAR FROM YOU. Be sure to join the debate on abcnews.com and yahoo.com where you can weigh in with your feedback in real time: http://news.yahoo.com/elections/debate/

Download Yahoo's "Into Now" app on your mobile device and you can join the debate as its happening.

Don't miss our ABC/Yahoo! special live debate coverage at yahoo.com and abcnews.com beginning at 8:45 pm ET. ABC's Terry Moran anchors from Washington, DC and is joined by Yahoo! News Washington Bureau Chief David Chalian from the spin room in Des Moines. http://news.yahoo.com/elections/debate/

The Yahoo! News and ABC News team will once again join forces in live blogging the debate. You can follow along and weigh in with your thoughts here: http://news.yahoo.com/elections/debate/

TOMORROW ON "THIS WEEK" ABC News anchors and debate moderators Diane Sawyer and George Stephanopoulos will join Christiane Amanpour live Sunday morning on "This Week" to break down highlights from the Iowa debate showdown. ABC News senior White House correspondent Jake Tapper, senior political correspondent Jonathan Karl, and correspondent John Berman will also join Amanpour from Iowa to analyze how the candidates fared, and what comes next as the campaigns head into the final stretch. And Christiane goes one-on-one with Jon Huntsman in a "This Week" exclusive. The Republican candidate is skipping Iowa and putting all his chips on New Hampshire. Will his "Live Free or Die" state strategy revive his campaign? Then, the roundtable will examine key moments from Saturday's debate and from the campaign trail this week, with ABC's George Will, Democratic strategist Donna Brazile, and Republican strategist Leslie Sanchez in Washington, and Des Moines Register political columnist Kathie Obradovich from Iowa. http://abcn.ws/tcvH5C

THE VIEW FROM IOWA. ABC's Shushannah Walshe, author of "Good Morning Iowa," our new daily morning tipsheet covering everything you need to know in the Hawkeye State between now and the Jan. 3 caucuses, tracks down the GOP candidates today. http://abcn.ws/vaE2aB

Almost all of them are in Iowa and almost all are holding events - no doubt while also doing some last minute prep. Newt Gingrich, Rick Perry, Rick Santorum, and Michele Bachmann, are all attending a Veterans Presidential Candidate Forum in Des Moines this afternoon. Gingrich is also opening up his new headquarters in Urbandale. Mitt Romney's wife and son, Ann and Josh Romney, along with Tim and Mary Pawlenty are holding a rally at their Des Moines headquarters. Rick Santorum is also holding a town hall in Jefferson and visiting a tree farm in Cumming with his family to select a Christmas tree for their Urbandale Headquarters. Ron Paul has a town hall in Marshalltown.

This is the front page Des Moines residents are waking up to today: http://bit.ly/c1CZ8U

WEATHER: It's in the low single digits right now, but could get up to a sunny, but cold 37 degrees later today.

The Des Moines Register's Jennifer Jacobs has a must-read preview of tonight's debate with a handy what-to-watch-for guide: Here are some highlights: Does Gingrich try to play it safe, does he roll out something big, or does he go on the attack?; Is Paul able to pull off a debate performance where he doesn't insult non-libertarian-leaning Republicans?; Can Romney gain likability points while drawing necessary distinctions with Newt Gingrich?; How many times will Bachmann say she's from Iowa?; If Perry doesn't make any major mistakes and stays on message, could he be one who benefits if conservatives leave Gingrich for some reason?; Santorum has a bit of on-the-ground momentum in Iowa with endorsements, so could a shining debate performance give him some mojo heading into the last few weeks? Read the entire piece here: http://dmreg.co/w3WZiy

THE WISE MAN OF IOWA. Iowa Gov. Terry Branstad's communications director Tim Albrecht offers his insights on debate day. Take it away Timmy: "I'll be watching how Newt deflects his criticisms in tonight's debate. He's been masterful at using the 'we shouldn't train our fire on fellow Republicans and should instead focus on President Obama…' which would yield a huge applause and be on a constant cable TV and talk radio loop over the following 48 hours. Can any candidate land a glove on Gingrich that shakes him off his 'shame on you media/opponent' meme?"

-ABC News and Yahoo News partnered again to bring you a pre-debate profile on conservative-and controversial-radio talk show host Steve Deace: "I want to make sure that the candidates get a thorough vetting to the point that they don't want to come back to Iowa again…That we gave them an ideological, moral proctology exam," Deace said.

-Read the profile: http://abcn.ws/uQtSSk and watch the accompanying web video: http://abcn.ws/uLA6Ui

@ karentravers : Health food in Iowa-steak an eggs W/ @matthewjaffe @emilystanitz pic.twitter.com/bZgJQ05N

READ ALL OF TODAY'S "GOOD MORNING IOWA" (GMI): http://abcn.ws/vaE2aB

THE BUZZ

ROMNEY ON HIS FAMILY-MAN AD: More from David's Muir's exclusive sit-down with Mitt Romney: Questioned specifically about his recent television ad, "Leader," which touts Romney's family values, the candidate told ABC News that the ad was not intended to be a veiled swipe at Gingrich. "Actually, in each of my campaigns, I've begun advertising season with an ad about me and my family and my values," he said. "There was no attempt to in any way to implicate anybody else in that," he said. "I'm just trying to let people know who I am." As for whether Gingrich's personal life - specifically his three marriages - should be considered a liability, Romney said he would "not give advice to the American people as to what they should look when they decide who should be their nominee or their president." "I'm not going to tell them which things they're allowed to consider," Romney said, "and which things they're not." -ABC's Emily Friedman

WATCH more: http://abcn.ws/sVDs5Q Tune into "World News" tonight for more highlights from Muir's interview.

DEMOCRATIC COUNTER-PROGRAMMING. ABC's Devin Dwyer notes that while two GOP frontrunners are headed for a face-off tonight, for Democrats, the focus remains on one man alone: Mitt Romney. In a pre-debate memo to reporters, Democratic National Committee vice chairman and Minneapolis Mayor R.T. Rybak doubles down on the party's critique of the former Massachusetts governor, while only briefly mentioning former House Speaker Newt Gingrich - despite his rise in the polls. Rybak says Gingrich's challenge of Romney in Iowa, evident in the most recent ABC News/Washington Post survey of likely caucus goers, has forced the once presumptive GOP nominee to "abandon his general election playbook in favor of a sharp turn to the right." http://abcn.ws/vTdcsV

GINGRICH: I LIKE THE PRESS. ABC campaign digital journalist Elicia Dover files a reporter's notebook from the campaign trail with Newt Gingrich: Most people who follow Republican presidential candidate Newt Gingrich around constantly either work for him or are members of his family. As an ABC News political '"embed'" with the Gingrich campaign, I'm certainly neither, but when a presidential candidate's schedule is your schedule, it provides a unique opportunity to get to know a person who very well could play a role in shaping the country for the next eight years. While it would seem likely that Gingrich would find a camera in his face annoying, he told ABC News that he likes it. "I actually identify with the people who are the embeds," Gingrich said. "Also, we have really nice people. I mean all the guys who are hanging out with me are nice. I don't know about the other campaigns." But is he ever worried we'll catch that embarrassing moment or that he will say something he shouldn't? "Sooner or later, everything gets covered in the modern world and if you didn't do it, somebody with a cellphone camera would do it," Gingrich said. http://abcn.ws/uALAkr

ANN ROMNEY CALLS MITT 'MY MOST DISOBEDIENT CHILD' Ann Romney has five children, but if you ask her, she actually has six. "Mitt is not what you think at home," Mrs. Romney said at a campaign event on Friday designed to court women voters in Iowa. "He is my most disobedient child." Her attempts to create an atmosphere of "family decorum," were constantly thwarted by Mitt, who Mrs. Romney said "liked to get them going and get them riled up." At Friday's gathering, billed as a "Women For Mitt," event, Mrs. Romney stuck to her Mitt-as-family-man script - one that she has been driving home with renewed intensity as the Romney campaign seeks to sharpen the contrast with Newt Gingrich. Her goal over the next few weeks, she said, will be to talk to voters about "the other side of Mitt that you never hear about." She never once mentioned Gingrich, who has been married three times, but her message was unmistakable. "The quote that we kind of grew up with as a motto in our home was, 'no other success can compensate for failure in the home,'" Mrs. Romney said. "That was something that was reinforced by Mitt all the time, and he had that basic value from that early, early time in our marriage." http://abcn.ws/s9x1g2

RICK PERRY GETS PERSONAL. Texas Gov. Rick Perry revealed a bit of his softer side yesterday, describing the most joyous moment in his life as his son's birth, an ordeal that nearly claimed the life of both his wife, Anita, and his now 28-year-old son, Griffin, ABC's Arlette Saenz notes. "'Nita was in labor for 40 hours, and her dad's a physician. She was the director of nurses at the hospital. We were living in the little town of Haskell [Texas], which was where she grew up, population of 3,500, 4,000, so she had a very difficult delivery," Perry recounted in an hour-long radio interview in Iowa with WHO radio's Simon Conway. "It was a weekend and the anesthesiologist couldn't come, and her father literally said, 'If we don't get her out of here to Abilene, I'm afraid we're going to lose the baby and her.' So not words you want to hear as you're, you know, the woman you love and your first born is being there." http://abcn.ws/umyuam

RICK SANTORUM NABS BIG IOWA ENDORSEMENT. ABC's Shushannah Walshe files this dispatch from Johnston, Iowa: Rick Santorum got his biggest endorsement yet at a small hotel here: Iowa Secretary of State Matt Schultz. Calling it the "best day of the campaign," he said he is "committed to Iowa" and the campaign is beginning to "pick up that critical momentum," despite his low poll numbers. "People have asked me, 'Why haven't you started to catch on?' And I say, 'Well you haven't been in Iowa for the last week or so because we are definitely picking up momentum in the state of Iowa and across this country.' We feel it coming," Santorum told a crowd of more than 50 people at the Stoney Creek Inn here. During the previous election cycle, Schultz endorsed Mitt Romney, a fellow Mormon, and Santorum said the endorsement was "a great reaffirmation of the work we've done." http://abcn.ws/sxG39B

WHO'S TWEETING?

@ mattstrawn : MT @JenniferJJacobs: Details on tonight's GOP prez debate in IA: how to watch, join a live chat.. dmreg.co/sXNpdw #iacaucus #iowadebate

@ jaketapper : Met a few Iowa voters - conservative Republicans - who don't like Perry's TV ads. They want to hear about jobs, not gays and skl prayer.

@ TheFix : Newt Gingrich, zoo lover. (Not a sarcastic headline). ow.ly/7V53i

@ jmartpolitico : In DSM RT @maggiepolitico: Glut of ads is unreal. Mitt SuperPAC negative spot has aired twice in the last 40 mins. 60 sec spot…

@ JimPethokoukis : So is Romney in the Pawlenty position where if he doesn't follow thru on Newt attacks, it looks weak?

POLITICAL RADAR.

-Newt GINGRICH attends a Veterans Presidential Candidate Forum at the Varsity Theater in Des Moines and later heads to the grand opening of his Iowa Campaign Office. A book signing with Callista will follow.

-Ann and Josh ROMNEY, Tim and Mary Pawlenty hold Iowa grassroots rally at Romney for President Headquarters in Des Moines.

-Rick PERRY takes a jog through Des Moines this morning and attends a Veterans Presidential Candidate Forum at the Varsity Theater in Des Moines later today.

-Rick SANTORUM will host host a "Faith, Family, and Freedom" Town Hall at Abundant Life Ministries in Jefferson, Iowa this morning, visit Howells Tree Farm in Cumming, and attends a Veterans Presidential Candidate Forum at the Varsity Theater in Des Moines this afternoon.

-Ron PAUL holds a town hall meeting at the Fisher Community Center in Marshalltown, Iowa.

-Michele BACHMANN attends a Veterans Presidential Candidate Forum at the Varsity Theater in Des Moines this afternoon.

-Jon HUNTSMAN holds a town hall meeting in Londonderry, NH.

-9:00pm - 11:00pm ET - ABC News, Yahoo! News, Des Moines Register, WOI-TV, Iowa Republican Party, Presidential Debate at Drake University. Diane Sawyer and George Stephanopoulos will moderate.

-ABC's Joanna Suarez and Josh Haskell

Check out The Note's Futures Calendar: http://abcn.ws/ZI9gV

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