WASHINGTON (AP) -- Hardening battle lines for the brawl to come, President Barack Obama urged congressional Democrats to "look out for the American people" in defending his legacy health care overhaul, while Vice President-elect Mike Pence stood firm Wednesday in telling Republicans that dismantling "Obamacare" is No. 1 on Donald Trump's list.
"We're going to be in the promise-keeping business," Pence declared at two separate Capitol news conferences. Just 16 days before Trump takes over the Oval Office, he said repealing and replacing Obama's law will be the president-elect's "first order of business."
"The American people voted decisively for a better future for health care in this country, and we are determined to give them that," Pence said.
Outnumbered in the new Congress, Democrats didn't sound confident in stopping the Republicans cold but signaled they wouldn't make the GOP's job any easier. New Senate Minority Leader Chuck Schumer, D-N.Y., said that if the Republicans do scuttle the health care law, they will have to come up with a replacement plan before Democrats consider whether to help them revamp the system.
That adds pressure on Republicans, who for years have battled among themselves over what a new law would look like, including how to finance its programs and whether to keep Obama's expansion of Medicaid for more lower-income people.
"They're repealing, we're not. It's their obligation to come up with a replacement," Schumer said, a sentiment he said he believed Democrats shared unanimously.
Obama and Pence held dueling strategy sessions with lawmakers at the Capitol as the new Republican-led Congress commenced its drive to dissolve the health care statute. The 2010 overhaul, which has extended coverage to 20 million people and reshaped the nation's $3 trillion-a-year health care system, has long stood as one of Obama's proudest triumphs and the ascendant GOP's top target for extinction.
"Despite the negativity you have a big chunk of the country that wants this thing to succeed," Obama told Democrats, according to an aide who attended Wednesday's session.
The two sides traded insults through the day.
"Don't let the Schumer clowns out of this web," Trump wrote on Twitter.
Said Schumer: "The Republican plan to cut health care wouldn't make America great again, it would make America sick again."
Previewing an attack line sure to be heard again in this year's debate, House Minority Leader Nancy Pelosi said the GOP is aiming to also scuttle Medicaid and Medicare, going after programs that are "very personal in the lives of the American people."
Even with White House and congressional control, annulling "Obamacare" and replacing it looms as a daunting task for the GOP.
Leaders hope to have legislation voiding much of the law on Trump's desk by late next month, Republicans said. But after six years of failing to unite behind an alternative, GOP leaders are discussing postponing when repeal would take effect for 18 months or longer, allowing more time to craft replacement legislation.
Underscoring the law's widespread constituency, the Obama administration said at least 8.8 million people signed up through Dec. 31 for coverage in 2017. Even so, outside experts doubt the administration will meet its nationwide target of 13.8 million signups.
Millions more have coverage under the statute's Medicaid expansion.
Trump has provided few details about how he would redesign the law, but has said he wants to retain popular provisions like ensuring coverage for people with pre-existing medical problems.
Republicans will also need to figure out how to protect health coverage for millions of Americans during a transition period and how to avoid market-place bedlam as nervous insurance companies stop selling policies or boost rates. Seemingly acknowledging that danger, Trump tweeted warnings to GOP lawmakers.
"Massive increases of ObamaCare will take place this year and Dems are to blame for the mess," he wrote. "It will fall of its own weight -- be careful!"
Republicans said Pence told them in their private meeting to argue that Democrats broke the health care system and Republicans will fix it.
Trump's team is already working with GOP congressional leaders on plans to undo Obama's law with both legislation and executive action that the president and federal agencies would be able to take, Pence said. Lawmakers said that according to Pence, Trump would sign some orders the day he takes office.
Pence did not specify what those actions would be. But House Speaker Paul Ryan, R-Wis., told reporters they would involve "transition relief."
In the Democrats' meeting, Obama accepted some blame for not sufficiently promoting it.
"The president said, I guess we all could have done a better job of messaging to the American people," said Rep. Joe Crowley, D-N.Y.
Obama made his remark about looking out for the American people as he left the meeting.
Meanwhile, the Senate voted 51-48 Wednesday to begin debating a budget that, once approved, will prevent Democrats from using a filibuster to block future Republican legislation to void the health care law.
Republicans control the Senate by 52-48, but it takes 60 votes to end a filibuster, a procedural roadblock that can kill legislation.
The Senate is expected to complete the budget by next week, with House approval to follow.
Associated Press reporters Ricardo Alonso-Zaldivar, Erica Werner, Mary Clare Jalonick, Richard Lardner, Stephen Ohlemacher, Kevin Freking and Andrew Taylor contributed to this report.