Washington (CNN) -- President Obama's departure for an upcoming overseas trip has been pushed back three days to help Democrats with a final push on health care reform.
Obama will leave for his trip to Indonesia and Australia on March 21 instead of March 18, White House press secretary Robert Gibbs announced Friday. The president previously expressed a willingness to delay the trip to work on health care, according to a senior administration official.
Obama, House Speaker Nancy Pelosi and Senate Majority Leader Harry Reid all agreed that having the president remain in Washington for an extra three days to help sway nervous congressional Democrats would be important, Gibbs said.
Both Gibbs and key Democrats on Capitol Hill said a wave of fresh momentum is bolstering efforts to overhaul health care.
Obama spent much of the past week pitching his health care plan to nervous congressional Democrats behind closed doors. He's also tried to boost public support for the plan, publicly calling for a final up-or-down vote in Congress while hammering the unpopular health insurance industry during visits to Pennsylvania and Missouri.
He's set to deliver another health care address Monday in Ohio.
The entire House Democratic caucus spent Friday morning reviewing the status of the nearly $1 trillion reform package. Pelosi said she was still waiting for a report from the nonpartisan Congressional Budget Office on the cost of changes to the Senate bill being negotiated by House and Senate leaders.
"I would hope that we [get the report] today," she told reporters on Capitol Hill. She also indicated the House would wait at least one week after the CBO report's release before proceeding to a vote in the full chamber.
Pelosi has promised that the House will wait at least one week after the CBO report's release before proceeding to a vote in the full chamber.
The speaker appeared to indicate Friday that the House would pass the Senate health care bill before Obama departs for his overseas trip on March 21.
"I'm delighted that the president will be here for the passage of the bill," Pelosi said. She immediately added a caveat to the timetable, however, saying she is only "hoping" that the bill will be passed "in that time frame."
Gibbs had said earlier in the week that he expected the House to pass the Senate bill by March 18.
A Democratic leadership source, however, said the legislative push would begin Monday when the House Budget Committee holds a key procedural vote starting the reconciliation process.
Reconciliation is a legislative maneuver that allows bills to be passed in the Senate with a simple majority of 51 votes. Senate Democrats lost their filibuster-proof 60-seat supermajority with the January election of GOP Sen. Scott Brown of Massachusetts to the seat formerly held by the late Democratic Sen. Ted Kennedy.
Republicans are furious over the Democrats' decision to use the procedure. They contend that reconciliation, which is limited to provisions pertaining to the budget, was never meant to facilitate passage of a sweeping reform measure such as the health care bill.
Reid dismissed the GOP complaints in a letter sent Thursday to Minority Leader Mitch McConnell, R-Kentucky. "Reconciliation would be used to make a modest number of changes to the original legislation, all of which would be budget-related," Reid said. "There is nothing inappropriate about this."
If the House approves the Senate version of the health care bill, a separate package of changes designed in part to make the overall measure more palatable to House liberals then would be approved by both chambers using the reconciliation process.
Liberal House Democrats contend, among other things, the Senate bill does not include an adequate level of subsidies to help middle- and lower-income families purchase coverage. They also object to the Senate's proposed tax on expensive insurance plans.
At the same time, a handful of socially conservative House Democrats argue the Senate plan doesn't do enough to ensure taxpayer funds are not used to fund abortions. Several political analysts have said lingering divisions over abortion may prove to be the toughest hurdle for Democratic leaders to overcome.
Multiple Democratic sources -- including House Majority Leader Steny Hoyer of Maryland -- also have said a large student loan reform measure likely will be rolled into in the health care reconciliation package. The measure, which is a priority for Obama, would end the practice of having private banks offer student loans while expanding direct lending from the government.
McConnell ripped the idea while speaking to reporters in a conference call Friday. It shows "the length [Democrats] are willing to go to have the government expand its tentacles into absolutely everything," he said.
The Democrats are "twisting themselves into pretzels" trying to get health care passed, he argued. "The reason all of this arm twisting ... is going on is because people hate this bill."
Adding to Democrats' headaches: a ruling by the Senate parliamentarian Thursday that the Senate health care bill must be signed into law by the president before a package of changes can be approved through reconciliation.
A number of House Democrats are nervous that the more conservative Senate will fail to follow through on promised changes to the bill once it becomes law. Democratic aides have admitted that it would be easier to vote on the original Senate bill if it were immediately followed by a vote on the package of changes in reconciliation.
Republicans see the parliamentarian's decision as a tactical victory, making the climb to health care passage steeper.
Pelosi, however, expressed confidence Friday that the Senate would carry through on any agreement reached between the two chambers. She noted that Senate Republicans had only been able to obstruct Democratic legislation by deploying the filibuster and requiring Reid to find 60 votes to pass most bills -- a hurdle which doesn't exist under reconciliation.
House members are receiving "certain assurances they want" from the Senate, she said, without specifying any details.
The process "will take a little faith, but what we do always does," she said.
Democrats also have one other option. They could try to tie the changes they want in the Senate health care bill to other laws currently on the books. But it's not clear if that is feasible, especially because some key issues in the health care bill -- such as how to pay for reform -- are not found in existing laws.
CNN's Ted Barrett, Lisa Desjardins, Suzanne Malveaux, Alan Silverleib and Deirdre Walsh contributed to this report.