With health care reform at the top of President-elect Barack Obama’s agenda next year, Democrats who have salivated over the opportunity to revamp the nation’s health care system for decades are having to walk a fine line as they seek to work together on what promises to be a historic legislative endeavor.

Of course, playing nice doesn’t necessarily come naturally to some of the key players in the debate, and many of them have a storied history of attempting to elbow others out of the way.

To begin with, Democrats are wary that the once-open rift between Health and Human Services Secretary nominee Tom Daschle and Senate Finance Chairman Max Baucus (D-Mont.) could rear its head again in the coming months.

Additionally, some Democrats have questioned Baucus’ decision to issue his principles for health care reform after Senate Health, Education, Labor and Pensions Chairman Edward Kennedy (D-Mass.) privately asked Members to refrain from proposing competing legislation.

Then there’s Sen. Hillary Rodham Clinton (D-N.Y.). Though she doesn’t wield much seniority and likely could end up a nonissue if she becomes Obama’s nominee for secretary of State, Clinton has a tremendous amount of credibility on health care. Earlier this fall, Kennedy rejected her attempt to secure a plum health care subcommittee chairmanship.

Last but not least, there is the issue of whether Kennedy will be able to manage all of the egos and jurisdictional disputes given his own uncertain health. Kennedy is battling brain cancer and underwent brain surgery earlier this year to minimize his tumor.

Still, most of the power players and their aides say everyone is mindful of the need to play nice to avoid the pitfalls of the Clinton administration’s failed universal health care plan, when Democratic infighting allowed Republican opponents to define the issue and sink the proposal.

And so far, it appears that is working. Kennedy has been working closely with Baucus, as well as with fellow HELP Committee members to draft a bill. Baucus and Daschle have spoken several times over the past few weeks about health care issues. And Clinton has been tapped by Kennedy to spearhead a working group on insurance coverage as he seeks to craft legislation based on Obama’s health care blueprint by the time Congress convenes in January for the 111th Congress.

“Nobody wants to be the one who clearly makes this thing fall apart,” said one Senate Democratic health care staffer.

Sen. Ron Wyden (D-Ore.), who as a Finance Committee member has pursued his own bipartisan health care legislation for years, said he is optimistic about the ability of the major players to get along.

“I’m very encouraged by the cooperation that I am seeing with the chairs — Chairman Baucus, Chairman Kennedy, with the incoming Obama administration,” Wyden said. “The reality is that the agreements on key issues are many more than there are potential differences in terms of strategy.”

Wyden added that he had a long breakfast with Daschle, the former Senate Majority Leader, on Thursday to talk about health care.

Baucus spokeswoman Carol Guthrie said Baucus and Kennedy are working to avoid jurisdictional spats.

“Sen. Baucus and Sen. Kennedy have been very explicit, publicly and privately, in their intention to work closely together on health care reform,” Guthrie said. “At the Senators’ direction, there is and will continue to be an enormous amount of cooperation and discussion among Finance and HELP staff behind the scenes on health reform. Americans need a new health system now, and Sen. Baucus has his eye on the ball, not on the turf.”

However, Baucus has raised some eyebrows by getting out in front of Kennedy in releasing an outline of his proposal last week. “Most people are shaking their heads, saying what is Baucus doing putting out a plan before Kennedy,” one well-placed Senate Democratic source said. “It was a bizarre move by Baucus.”

For his part, however, Kennedy publicly praised the move. “Senator Baucus’ white paper is a major contribution to the debate on health reform,” Kennedy said in a statement. “It provides an important analysis of the urgent need for significant improvements in our health care system, and thoughtful recommendations for reform.”

One former Senate Democratic staffer who knows the players said Baucus was not likely trying to big foot Kennedy as much as he was trying to get out in front of Obama — in part to make sure that Congress defines the debate and not the White House. The fact that the Clinton White House sent up its mammoth bill still produces some consternation among Congressional Democrats, who said they were presented with an all-or-nothing proposition from the administration.

“Everyone wants to jump ahead of [Obama],” the former staffer said. “They’re trying to jump out there with plans so he doesn’t have to offer his own plan.”

Wyden said Baucus did the right thing by moving quickly, and the former aide said he believes the Obama administration will not fall into the same traps as the Clinton White House did.

“An Obama administration is going to give a broader berth to the Congress,” Wyden said. “You’re not going to see them send a 1,360-page bill to Capitol Hill.”

Baucus also has a troubled history with Daschle. As Majority Leader in 2001 and 2002, Daschle often cut Baucus out of negotiations on legislation under the Finance Committee’s jurisdiction, primarily because Daschle did not trust Baucus’ faithfulness to Democratic wants.

But Guthrie said the two men have had several “very good conversations recently.”

Plus, any Baucus-Daschle tensions could be smoothed easily from within the White House, given former Baucus top aide Jim Messina will be serving as Obama’s deputy chief of staff.

Despite his health problems, Kennedy has been working the issue hard since returning to Washington, D.C., a few weeks ago, specifically to begin drafting health care reform legislation. And Senators and aides said that barring a decline in his health, Kennedy will certainly drive the debate in the Senate.

“The major player here is going to Sen. Kennedy and the [HELP] committee,” one senior Senate Democratic source said. “I expect that beginning in January, if his health holds, he’ll be taking ownership of this.”

Indeed, several aides said Kennedy did just that by making sure that Clinton had a seat at the table and a leadership role. The thinking is that it is better to have her working on the inside than building a competing coalition of support for her own proposals on the outside.

Kennedy and Baucus have been reaching out to Republicans, though Baucus appears to be getting more credit from the GOP at the moment.

“Obviously, [Baucus] is going to be the point guy on this in the Senate — along with Sen. Kennedy,” said Sen. Judd Gregg (R-N.H.), who said he has been contacted by Baucus about the issue.

Baucus and Kennedy also have been holding meetings with private and public sector stakeholders — such as insurers, health care providers, advocacy groups and the business community — in the debate to try to identify fault lines and points of contention.

One person whose group has been a participant in the meetings said that so far they have been “pretty productive” and that the debate has been “a dramatic improvement” over the Clinton-era health care debacle.

“It’s significant how different the landscape is,” the source said.