WASHINGTON-In a statue-lined busy Capitol Hill hallway just off the House floor, Congressman Allen Boyd, a moderate Democrat from Florida, outlined to a news camera all the reasons-repeated ad nauseam by lawmakers during the past year-why the nation's healthcare system needs changing. "So you are ready to support Obama's revised plan?" the television journalist interrupted. A larger-than-life statue of early 20th-century humorist Will Rogers, a slight smirk on his face, stood watching in a corner as Boyd replied, "Well, now I didn't say that."

Will Rogers, in top political satire mode, once said, "I belong to no organized party. I am a Democrat." Those words still ring true nearly a century later: It is Democrats against Democrats here as the healthcare debate moves toward a conclusion.

Indeed, Congress is tipping off its own version of March Madness just in time for the frenzy of the annual NCAA men's basketball tournament. But instead of 65 teams, this bracket contains the roughly 435 individual members of the House who are about to take what is sure to be the biggest vote of 2010. Despite yearlong efforts by both voters and Republicans to stop the Democrats' overhaul, the Democratic leadership is still fighting for Obamacare.

But in what could be healthcare's climax, House Speaker Nancy Pelosi is asking Democrats once again to put their careers on the line for a controversial vote that she and other leaders would like to hold before fence-sitting lawmakers face constituents during the Easter recess.

With this last healthcare battle to be fought in the House, don't be surprised if Pepto-Bismol sales suddenly spike at Capitol Hill-area pharmacies. Skittish House members are weary about going on the healthcare record again just four months after the chamber narrowly passed its $1 trillion plan last November, 220 to 215.

The margins have gotten tighter since then: The sole Republican yes vote, Rep. Joseph Cao of Louisiana, has said he will vote no on Healthcare Part Deux. And three of the 219 Democrats who voted yes are gone now through a death and two retirements.

That leaves Pelosi with exactly the 216 votes now needed to win a majority in the reconfigured House. But the idea that she actually has that number of votes may be Democratic optimism.

The focus is on the House because Democratic leaders have determined that their best hope in the post-Scott Brown-election world is to ask representatives to vote on the already-passed Senate version. But that contains one major problem for Rep. Bart Stupak, the pro-life Michigan Democrat who voted for the House's healthcare overhaul only after securing strong language forbidding the federal funding of abortion. That protective language is absent in the Senate bill and, so far, Stupak has signaled that he will choose principle over party.

Worse for Pelosi: Stupak claims he is one of a dozen Democrats ready to switch their healthcare votes from yes to no because the Senate bill could lead to taxpayer-funded abortions. If true, potential House yeses drop from 216 to 204. "Let me say this: This is not about abortion!" an exasperated Pelosi shouted to reporters last week. But at least a dozen of her House Democrats disagree.

What does this all mean? Her inflexibility when it comes to abortion, fueled by the pro-abortion lobbying machine, may kill the healthcare bill.

Three out of five voters in a recent poll agreed that abortion funding should have no place in healthcare legislation. These are numbers listened to by lawmakers who still want to be lawmakers next year. Since the Senate bill cannot be amended before the House votes, then the House will defeat the overhaul unless Pelosi is able to twist a dozen arms among the 39 Democrats who voted no last November. That's asking nearly a third of her colleagues to flip-flop in an election year when such a switch would lead to instant campaign commercials from rivals. Already the Cook Political Report lists 53 Democratic House seats as competitive in this year's election.

Where will Pelosi look to keep healthcare on life support? Here is WORLD's primer on a congressional drama that may rival this year's Final Four:

The Freshmen

Fourteen of the 39 Democrats who voted against the healthcare bill are new to Congress and cannot yet shield themselves behind the fortress of incumbency. That includes Maryland's Frank Kratovil, among the shakiest of House Democrats, whose margin two years ago was less than 1 percent of the vote in a district that was in Republican hands.

When a story circulated during the first week of March that Kratovil was undecided on his second healthcare vote, the National Republican Campaign Committee placed thousands of targeted phone calls to Kratovil's Eastern Shore district. By week's end Kratovil used GOP talking points to reassure voters that he would oppose the current healthcare bill.

"The way we are moving forward is perceived as all or nothing. I don't think it needs to be zero sum," Kratovil told the Capitol News Service, echoing the Republican refrain that healthcare is best tackled using a step-by-step approach.

"He is trying to protect his seat," says Diana Waterman, 48, who works for a real estate company in Kratovil's district. "If he votes in favor of this bill, it will be the last nail in his coffin."

Instead of orating about healthcare, Kratovil has been spending March touting a Republican-sounding small business tax relief proposal that he authored. Similar posturing by other Democratic freshmen suggests that Pelosi will find few takers here.

The McCain Democrats

Thirty-one of the 39 Democrats who voted no in November represent districts won by Sen. John McCain in the 2008 presidential election-including Florida's Allen Boyd, interviewed near the Will Rogers statue. No word on whether Boyd repeated his TV camera healthcare backpedal ("Now, I didn't say that") later that same day when he was one of 31 Democrats invited to a private White House reception. No doubt arm-twisting occurred there as President Obama continues to look for a way to declare any healthcare victory.

Pelosi has publicly asked colleagues to vote for healthcare even if it jeopardizes their political careers. But the Democratic leadership's best Shakespearean "band of brothers" speeches have so far not rounded up even a "happy few" in the McCain districts willing to follow Pelosi's charge. Of course, the seats of Pelosi and House Majority Leader Steny Hoyer are secure, while the same thing cannot be said for these McCain Democrats.

The Fiscal Conservatives

Most fiscally conservative Democrats, known as Blue Dogs, are refraining from going on the healthcare hunt. Of the 39 Democrats who voted against healthcare in November, 24 are Blue Dogs, who prefer cost containment measures to coverage expansion. Rep. Jim Marshall, a Blue Dog from Georgia, told Fox News this week that Obama's healthcare plan equals "continued explosive costs. We're bankrupting the country over this."

This concern is not just limited to Southern Blue Dogs: Rep. Stephanie Herseth Sandlin, a South Dakota Democrat and leader of the Blue Dog coalition, told reporters she will "not vote for the Senate bill as is."

House members are being asked to vote for a Senate bill with the promise that some of its less palatable elements will be tenderized in a revised version that would then have to pass the Senate with just a simple majority. That means Blue Dogs would have to approve a bill that is loaded down with controversial, budget-busting kickbacks to states like Nebraska, Louisiana, and Florida.

"What they are asking House Democrats to do is to hold hands, jump off a cliff, and hope [Senate Majority Leader] Harry Reid catches them," explained Lamar Alexander, the Tennessean who is the Senate's third-ranking Republican.

"The Senate has given us a lot of reason not to trust them," Blue Dog Rep. Jason Altmire, D-Pa., who is listed as a top prospect for switching his no vote, told Fox News Sunday.

The Retirees

Six House Democrats who opposed the healthcare bill in November are retiring this year. They are being pressured to change their votes as a legacy to their party since they no longer will have to face constituents.

Perhaps preparing for such a flip, one of these retirees, Rep. Bart Gordon, D-Tenn., released a statement praising Obama's revised plan as moving in a "more fiscally responsible direction." But another retiring Democrat, Rep. Brian Baird of Washington, told CNN that "I don't think this bill is what I would like to see us do."

Meanwhile, another exiting Democrat who voted for the overhaul, Rep. Marion Berry of Arkansas, could switch to a no vote after he ripped the White House for marginalizing moderate Democrats during his retirement announcement.

The Heritage Foundation's House expert, Eric Heis, sees "more people going from a yes to a no than from no to yes. They are scared about losing their seats."

Of the Democrats who voted for the overhaul, 18 reside in districts won by McCain in 2008, and they are likely reconsidering their yes votes.

Forced to vote on a Senate healthcare bill that they have repeatedly blasted as inferior to their version, their armor may soon start to crack. And groups like pro-life Susan B. Anthony List (spending $500,000 for a three-week campaign) and the League of American Voters ($250,000 a week) are helping the fissure through a barrage of mailings, automated calls, and television and radio ads in Democratic districts. While no November yeses have yet announced a switch, at least one, Rep. Michael Arcuri of New York, is leaning toward voting no: "There would have to be some dramatic changes in it," he told the Utica, N.Y.-based Observer-Dispatch. Other yes lawmakers from North Dakota, Oregon, Nevada, California, Pennsylvania, Ohio, and Virginia have refused to commit when pressed by local media.