Bipartisan Senate Finance Committee health care talks were teetering on the edge Tuesday as Chairman Max Baucus (D-Mont.) struggled to win over two key GOP negotiators in advance of President Barack Obama’s speech to a joint session of Congress on Wednesday night.

Hoping to seize some momentum from the president’s prime-time address, Baucus on Tuesday tried to force a deal out of the gang of six Finance negotiators, but was met with a cool reception by ranking member Chuck Grassley (R-Iowa) and Sen. Mike Enzi (R-Wyo.).

Obama is set for the first time to offer detailed policy prescriptions, which may include suggestions made by Sen. Olympia Snowe (Maine), the third GOP negotiator in the Finance talks. And without a bipartisan bill to point to, Senate Democratic leaders are preparing to hew closely to the president’s outline, sources said.

Baucus said his preference is to come to an agreement before the president lays out his own plan this evening, and Baucus gave the group until 10 a.m. Wednesday to present counterproposals “to see if we can reach an agreement sometime during the day.— The group is scheduled to meet in person this afternoon.

“In the afternoon, I’ll have to make a judgment as to where we’re at,— Baucus said after a meeting of the six Senators on Tuesday evening. He left open the possibility of reaching an agreement after the president’s speech but said regardless he would call for a markup of the bill “over the next week or so.—

Grassley and Enzi declined to endorse or reject the proposed policy framework Baucus floated over the weekend. But one Senate Democratic source said Grassley and Enzi have told the chairman that they would have a hard time signing on to it.

After Tuesday’s meeting, a cautious Enzi would only confirm that he remains a part of the negotiations, saying, “I don’t try and negotiate any of this stuff through the press.—

In a sign of how precarious the talks are, Grassley and other negotiators largely evaded the press after the meeting. However, sources said Grassley and Enzi were leery of Baucus’ suggestions for financing his plan such as levying hefty fees on insurance companies and other health care stakeholders.

[IMGCAP(1)]In their statements over the August recess, both Grassley and Enzi downplayed the group’s ability to reach consensus as well as their own roles in the process, and they have come under pressure from Senate GOP leaders to reject any deal that cannot be supported by a broad swath of their Conference.

If Grassley and Enzi decide to reject Baucus’ offer, Democratic aides said, the focus will formally shift to Snowe and her home-state colleague and fellow moderate Sen. Susan Collins (R-Maine), as well as to the task of shoring up wavering centrist Democrats. Snowe, who Democrats believe is the only GOP Finance negotiator who will remain at the bargaining table, expressed some reservations with Baucus’ proposal, but said she found much to like about it.

“There are a number of promising elements,— she said before Tuesday’s meeting.

In addition to her talks in Finance, the White House has been actively courting Snowe by indicating interest in her proposal to create a public insurance option as a fallback only if private health insurers cannot cuts costs and increase coverage on their own. Sources said the White House was involved in helping Baucus settle issues that the gang had not yet agreed to and that administration officials provided suggestions for how to keep Snowe interested. However, Snowe’s “trigger— proposal for a public insurance plan is not included in Baucus’ proposal.

Baucus said he was not open to a wholesale rewrite of his plan, which includes most of what the six negotiators agreed to during their months of talks. However, the measure could spark opposition from some corners of the Democratic Conference because it ignores liberal calls for the creation of a public insurance option. Instead, it would create a network of nonprofit health insurance cooperatives, which receive their seed money from the government but otherwise operate independently.

The votes from the two Maine Senators would not necessarily make Majority Leader Harry Reid’s (D-Nev.) task of building a 60-vote majority less complicated.

After meeting with the president at the White House on Tuesday, Reid acknowledged that moving health care reform as a largely partisan bill under filibuster-proof budget reconciliation rules would not achieve as much as legislation passed under regular order and with Republican votes.

“We can get it through that way, but it’s not as robust a bill,— Reid said. Reid was not specific about what would have to be left out. He also said he expects a markup of legislation by Baucus next week.

Reid’s staff has been preparing for the likelihood that in the end they may not have any Republican votes and may lose some centrist Democratic votes. Over the August recess, Reid’s staff began preparing a health care proposal to fit within stringent reconciliation rules, which would protect the measure from filibuster but limit the scope of the bill because every provision would have to have a budgetary impact.

Reconciliation could be the only way to pass a measure in the Senate considering that Democrats have little room for error. Following the death of Sen. Edward Kennedy (D-Mass.) last month, the Senate Democratic majority is only 59 strong.

The six on Finance members — Baucus, Grassley, Enzi, Snowe, Sen. Kent Conrad (D-N.D.) and Sen. Jeff Bingaman (D-N.M.) — have been deliberating since June, and Baucus had originally given the group until Sept. 15 to come to a deal. He accelerated his timeline once Obama announced last week that he would speak to a joint session of Congress on Wednesday.

Keith Koffler contributed to this report.