Demonstrators rally against a partial government shutdown at a protest hosted by the National Air Traffic Controllers Association (NATCA) on Capitol Hill in Washington, D.C., U.S., on Thursday, Jan. 10, 2019.

The longest government shutdown in U.S. history is finally over. Now lawmakers from both parties are seeking a way to ensure it never happens again.

Several proposals are on the table. They go beyond the immediate discussions over border security that will need to be resolved over the next three weeks, when the government could once again run out of money.

Instead, these bills would guarantee that the lights stay on even if lawmakers can't reach a spending agreement by Feb. 15, or any future date.

At the heart of the proposals are continuing resolutions that would keep government funding unchanged and automatically take effect during any lapse in appropriations. Lawmakers wouldn't have to debate whether to take action — it would just happen.

"We have to put an end to budgeting by crisis, and auto-CRs are a very reasonable approach," said Maya MacGuineas, president of the Committee for a Responsible Federal Budget. "Of course, our political leaders should actually do their jobs and pass thoughtful budgets, but given how often they routinely demonstrate that cannot be counted on, this would take the damaging shutdown threat out of the equation."

One of the idea's most vocal supporters on Capitol Hill is Republican Sen. Rob Portman of Ohio, who has introduced the proposal in every session of Congress since 2010. His bill has 19 co-sponsors, including Senate Finance Chairman Chuck Grassley, Alaska moderate Republican Lisa Murkowski and GOP conference chairman John Barrasso.

Portman said he is urging lawmakers to include the measure as part of any deal to fund the government by Feb. 15.

"Let's do something about it now while the pain and inefficiency of this moment is fresh on our minds," he said Friday.

House GOP leadership also signaled openness to the idea. On NBC's "Meet the Press" on Sunday, Minority Leader Rep. Kevin McCarthy said he supports an automatic funding measure but would amend it to ensure that lawmakers and their staffs would not get paid until a spending deal is reached.

Democrats also appear to be warming to the plan. House Speaker Nancy Pelosi expressed tentative support for the idea on Friday during a lunch with columnists, saying she hopes it's something "we might be able to put forward."

Democratic Sen. Mark Warner introduced legislation earlier this month instituting an automatic continuing resolution. The bill is titled the Stop Shutdowns Transferring Unnecessary Pain and Inflicting Damage In The Coming Years Act, or simply Stop STUPIDITY.

"Workers, business owners and tax payers are currently paying the price of D.C. gridlock and my legislation will put an end to that," Warner said in a statement.

But there is still plenty of partisan politicking around a proposal that ostensibly aims to end the damaging effects of partisan politicking. One critical difference between the Republican and Democratic bills is the level of automatic spending.

Portman's proposal would reduce federal spending by 1 percent if lawmakers do not reach an appropriation agreement within 120 days — and another 1 percent every 90 days after that until a deal is reached. Experts say the cuts are intended to ensure that the automatic spending levels do not become an easy way out for lawmakers reluctant to wrestle with thorny appropriations bills.

"It's probably not the right approach to fixing this issue," said Shai Akabas, director of the Economic Policy Project at the Bipartisan Policy Center. "A CR, while it's certainly better than a shutdown, is pretty much the next worst thing. If we make it easier to do a CR by making it automatic, we're probably going to have a lot of CRs."

Portman's baked-in spending cuts also make his proposal a nonstarter for many Democrats. A spokeswoman for Warner called it "sequestration by another name."

Warner's proposal would adjust the automatic spending level for GDP growth. The only portions of the government not covered would be the White House and the legislative branch.

"It's a just more neutral default option," said Seth Hanlon, senior fellow at the Center for American Progress and a former Obama aide. "Senator Warner's bill doesn't try to stack the deck one way or the other. It just aims to prevent shutdown."

Still, the length and cost of the most recent shutdown are stoking growing interest in the idea. The Congressional Budget Office on Monday estimated the damage to the economy at $11 billion, with $3 billion of economic activity permanently lost. And in just three weeks, lawmakers could be standing on the brink of shutdown once more.

"It's not supposed to be ideal," Hanlon said. "It's just a tradeoff between the need for Congress to set priorities and the need to prevent a shutdown."