President Obama told Democratic lawmakers Wednesday that he envied the position they were in to battle Republicans on the front lines in the halls of Congress.

"I envy you so much," he said, according to lawmakers in the room during their closed-door meeting. "Because I would love to be on the field right now ... You're privileged to be in the arena."

He traveled across town for a rare meeting on Capitol Hill with Democrats and, according to members of Congress and aides in the room, told them to stand their ground and fight Republicans over every attempt to repeal his signature policy achievements, particularly the Affordable Care Act, or "Obamacare."

Republicans are set to begin debate today over a budget resolution that could lay out instructions for repealing the law.

During today's meeting, Obama sought to remind Democrats that many pieces of the law are still popular with voters and that doctors and hospitals were worried about changes that could upend people's access to insurance.

"Despite the negativity, you have a big chunk of the country that wants this thing to succeed," Obama said, according to aides in the room. Sources said he emphasized that "real lives were at stake."

"That the country is clamoring to undo this thing is simply untrue," he continued, sources said.

Obama offered advice on political and legislative strategy and encouraged members to focus on telling stories of how the law has affected people's lives as well as to attend town halls in their districts. Many Democrats have said that if they play their cards right, they think Republicans could suffer major political fallout if they attempt to repeal or defund the law without a plan for replacing it.

After the meeting, Sen. Dick Durbin, D-Ill., said, "[Republicans] are inviting chaos. Unless they have something better to start with, it is irresponsible for Republicans to repeal 'Obamacare.'"

Since passing the law, Democrats have lost their majorities in the House and Senate, and several lawmakers in the room today faced tough political battles at home over the controversial legislation.

During the meeting, Obama took responsibility for some the political troubles with the law. "I will take the responsibility for not having fully communicated with the American people for why this is an extraordinary victory for them," he said, according to aides in the room.

Over and over, members leaving the meeting expressed a desire to unite as a party and fight.

"When they try to hurt the progress we've made on quality health coverage, we're going to be engaged. We're going to fight with everything we have," Sen. Ben Cardin, D-Md., said. "It's not politics for us. It is the people we represent who are going to be at risk."

"[Obama] encouraged us to fight, which we already made clear we are going to do anyway," Rep. Elijah Cummings, D-Maryland, said after the meeting. "President-elect Trump made it clear that we would not have people dying in the streets. We are going to hold him to that. I think the question that has to be asked of the Republican Party is, are you making things worse for the American people or better?"

House Democratic Caucus Chairman Joe Crowley, D-N.Y., introduced Obama and reminded his colleagues that the fight over health care was just one of many they expected.

"Keeping a rein on big banks, protecting the environment, ensuring workers are paid fairly, that immigrants feel welcome, that civil rights are upheld," he said. "All of these are the fights we are facing and that we must start to prepare for now. It's not just President Obama's legacy that is at stake. It is our values as Democrats and as Americans."