Getting to the 100th day in the White House is a major milestone for any new president. But because of a case of truly unfortunate timing, Donald Trump’s 100th day in office could also be the day that the federal government shuts down unless Trump and a bipartisan majority in Congress pass a major spending bill to lock in federal funding for the rest of the year.

But how will President Trump get an agreement on a difficult piece of legislation that he must pass when he’s had so much trouble managing bills that he and congressional Republicans wanted to pass?

A Politico/Morning Consult poll last week showed just how high the stakes are for Trump and Republican leaders when it comes to keeping the government running past April 28. A large majority of voters, 65 percent, think Congress should use “all means necessary” to avoid a government shutdown at the end of the month.

Just 17 percent said they could accept a shutdown “if it helps achieve their policy goals.”

Do you know what else had a 17 percent approval rating? The GOP health care bill that was so toxic last month that Republicans never even put it on the floor for a vote.

Fore-closed

With numbers like that, it’s easy to imagine a CNN countdown clock and a split screen showing “Park Closed” signs ready to go up outside of Yosemite while President Trump tees off near Mar-a-Lago. It won’t be a good look.

The good news so far is that Republicans and Democrats on the Appropriations committees have been meeting and negotiating on the details of a spending bill for months. Both sides understand each other’s priorities and neither side, especially Republicans leaders, seems interested in forcing a government shutdown for any reason.

But according to people close to the negotiations, the biggest wildcard and the most serious potential stumbling block is President Trump himself. Working among themselves, appropriators have found the general parameters of an agreement coming together. But what will happen when President Trump focuses on the details of the spending bill and sees something he doesn’t like?

Health care reform should have been an easy lift for a Republican president with Republican majorities and near unanimous agreement inside the party that repealing Obamacare was the right thing to do. They seemed to be on a glide path to repeal in early January until the president-elect spontaneously said he would insist on a much more complicated repeal-and-replace vote on the same day. Whether he’ll similarly weigh in on, and potentially derail, the spending bill is anyone’s guess.

When he does focus on the details of the negotiations, President Trump will find out quickly that Democrats have far more leverage this time around than they ever did in the health care fight. That’s because Republicans will need Democratic votes to pass a government spending bill that some conservatives and House Freedom Caucus members are likely to balk at.

Let’s make a deal

The president will also find out that the Democratic votes won’t come without concessions, and that those concessions are likely to make him crazy. The “beautiful wall” he wants to build on the southern border with Mexico? Democrats won’t allow a dollar for its construction in this spending bill.

And his promises to conservatives that he’ll defund Planned Parenthood if the organization continues to provide abortion services? He won’t get that or any other rider on this legislation if he wants Democratic votes to pass it.

Finally, when President Trump and Republicans look to increase spending for defense, Democrats will insist that money be matched with equal increases to nondefense discretionary spending, even though the president’s budget for next year proposes drastic cuts to domestic spending.

If the president thinks that using the threat of a government shutdown to gain leverage over Democrats is a good idea, he probably should think again. The last time Congress and the president failed to agree on a spending bill and let the government shut down in 2013, Congress’ approval rating fell to 12 percent. That’s Trump’s Congress now. 

And that’s to say nothing of how critical it has become for Congress and the president to start to fund the government strategically and deliberately, instead of lurching from CR to CR and showdown to showdown.

At a House Appropriations meeting, Gen. Mark Milley, the Army chief of staff, told House members how unacceptable the past reliance on continuing resolutions has been.

“Candidly, failure to pass a budget, in my view both as an American citizen and chief of staff of the United States Army, constitutes professional malpractice,” he said. Congress should pass this year’s funding bill and the supplemental spending bill, he said, “and get on with it.”

Roger that, General. Congress and the president should find a bipartisan agreement and keep the federal government open and operational. Otherwise President Trump’s 101st day in office will be running a government that isn’t running, working with a Congress that isn’t working, and instilling anxiety in an economy, a country, and a world that doesn’t need one more thing to worry about.

Just do your job and get on with it.

Roll Call columnist Patricia Murphy covers national politics for The Daily Beast. Previously, she was the Capitol Hill bureau chief for Politics Daily and founder and editor of Citizen Jane Politics. Follow her on Twitter @1PatriciaMurphy.Get breaking news alerts and more from Roll Call on your iPhone or your Android.