Updated

The entire Democratic Senate caucus is headed to the White House on Tuesday afternoon to talk health care with President Obama, just as the administration urges Majority Leader Harry Reid to cut a deal with Sen. Joe Lieberman, who is emerging as the skunk at the party for supporters of the massive package to create a new entitlement.

Lieberman opposes a proposal that would expand Medicare for people between the age of 55-64. Lieberman has also said he would oppose a government-run insurance option and on Sunday said that Senate leaders need to scale back the bill, removing both provisions from the final product, in order to get his vote.

Congressional staff familiar with negotiations said the White House is strongly urging Reid to work with Lieberman to eliminate the Medicare provision.

Sen Tom Harkin, D-IA, has conceded that the public option, once a top priority for him in healthcare reform, and Medicare buy-in are gone from Senate legislative efforts.

"It's not fair but it's reality," Harkin said, of the move precipitated by an announcement by Lieberman, that he would oppose the healthcare bill if those two items remain in it.

Reid and other Democratic lawmakers are said to be furious that Lieberman publicly called for the elimination of the proposal before members received an analysis by the nonpartisan Congressional Budget Office on the cost of such a plan.

Clearly inundated by calls to his office and a general backlash against his boss, a Lieberman aide told Fox News, "I want to emphasize, he would like to vote for a bill. He's not opposed to health care reform."

Democratic senators are meeting Monday night on the health care bill, and many are expected to voice their annoyance at Lieberman, the self-styled "independent Democrat."

"There are some people who are going to really want to get some frustration at Joe off their chest," one senior Senate Democratic aide told Fox News.

But, Sen. Evan Bayh defended Lieberman as he exited a special caucus of Democrats and reiterated that Medicare expansion was out of the bill.

:"there was no acrimony, no singling [him] out," said Bayh.

Some leadership aides said they thought Lieberman might not show up at the Monday night caucus meeting, but a Lieberman spokesman told Fox News the senator is likely to attend. Lieberman has said in the past that he will not attend purely political meetings.

Lieberman will attend Tuesday's healthcare meeting at the White House

The senator's senior aide said Lieberman's views are no surprise to Reid, who knew of the concerns as early as Thursday. According to the Lieberman aide, the senator's staff told negotiators last week, when the Medicare buy-in was developed, that he had problems with it. Lieberman sent a letter to Reid on Thursday and restated his concerns on Friday.

"It should not come as any surprise to the leadership what the senator's concerns were. Any contrary suggestions by Democrats under the cloak of anonymity are false and self-serving," the aide said.

The aide added that the senator does want to vote for a health care reform bill and sees "much good" in the existing bill, including insurance market reforms.

Lieberman, the aide said, sees the expansion of Medicare as "unnecessary" and "redundant" since Reid's original bill "already addresses the issues of access (with federal subsidies) and cost control."

His consistency on the issue came under question within hours, when House Democrats circulated a videotape from September in which he spoke favorably of allowing men and women as young as 55 to purchase coverage under Medicare.

Marshall Wittman, his spokesman, said those comments were made before the Senate health care bill, which includes health insurance subsidies, was finalized. He said Lieberman believes the government assistance makes a Medicare buy-in program redundant.

White House Communications Director Dan Pfeiffer said the president is not involved in the internal squabble between Lieberman and the majority leader.

"The White House is not pushing Senator Reid in any direction. We are working hand in hand with the Senate leadership to work through the various issues and pass health reform as soon as possible," Pfeiffer said.

But White House Press Secretary Robert Gibbs, who would not characterize the nature of Obama's involvement, said he's closely involved in the talks.

"The president is not agnostic to continuing to making progress on health care reform and trying to get it through the Senate," Gibbs told reporters Monday. "The president's been involved.
We wouldn't be sitting here the 14th of December, when you'd much rather be Christmas shopping, discussing the Senate being in on the weekends if the president wasn't involved. The president's been involved the whole time."

And congressional aides said the White House absolutely is urging Reid to make a deal though to say so is bad form in the minds of the Senate leadership.

After his Sunday show appearance, Lieberman met privately in Reid's office with White House Chief of Staff Rahm Emanuel, a fixture on Capitol Hill these days as health care reform gets hammered out, along with other key White House aides.

Even with anger directed at Lieberman -- echoed with far less diplomacy in the liberal blogosphere -- the caucus is fractured on a number of topics within the overall reform effort, and Obama must pull his former colleagues together around his top priority else risk the failure of the effort.

Some members have expressed varying degrees of skepticism about the bill in its current form, including the newest form of the so-called public option that's currently awaiting the CBO analysis.

The CBO could report as early as Tuesday on the cost of the Medicare proposal. A negative report could cost Reid the vote of Missouri Sen. Claire McCaskill.

Gibbs said he doesn't want to get ahead of the reporting since "CBO had told you all before that legislation bends the cost curve, the legislation would slow the growth rate in health care spending, that the health care legislation wouldn't add to the deficit but it would in fact help our fiscal situation. ...

"In terms of the specific policy, again, that's what the CBO is evaluating. And I think many on Capitol Hill await what they have to say," he said.

Lawmakers are also at an impasse over an amendment by Sen. Byron Dorgan, D-N.D., that would allow for the importation of cheaper drugs from an approved list of countries like Canada.

The Food and Drug Administration has taken a stand against the measure, and as a result, a handful of Democratic senators are blocking the Dorgan amendment. Dorgan in turn has said he will hold up all other action on the bill until he gets a vote.

Fox News' Trish Turner, Fox Business' Rich Edson and the Associated Press contributed to this report.