If President Trump really intends to build his border wall, spend tens of billions more on the military, slash social safety net spending, and enact any number of his other campaign promises in his first term, he had better hurry up. Because there is a good reason to think that he’s going to run out of time a lot sooner than he expects.

While it may seem alarmist to talk about a President running out of time when he’s only been in office for a little more than two months, a combination of factors, including Trump’s own unpopularity, the composition of the House Republican conference, and the changing face of the electorate might dramatically limit the new president’s influence with lawmakers in his first term.

Related: Tax Reform--A Must Win for Trump and the Republican Party

If history is any guide, the Republicans will lose seats in the House in the 2018 mid-term election. Some have even begun to speculate that with Trump’s approval ratings well under water already, the Democrats have a credible shot at taking control of the lower chamber, if not the Senate.

In 18 of the last 20 mid-term elections, the president’s party has lost House seats. And of those 18 elections, the average seat loss was 33. If that trend holds, the Democrats have a solid chance of picking up the 24 seats they would need to regain the majority.

While analysts caution that much can happen between now and 2018 – and that it’s always risky betting against Trump and his ability to shake things up and turn things around in his favor – a turnover in control of the House in 2018 would have a devastating impact on Trump and the Republicans and limit their ability to get anything passed in the future without Democratic support.

Even if the Democrats pick up no more than a dozen or so House seats, House Speaker Paul Ryan (R-WI) will face overwhelming odds against passing major legislation with his caucus split between the conservative Freedom Caucus and more moderate Republicans, and the Democrats positioned to make demands.

If that proves to be the case, Trump may have only limited time to achieve many of his major objectives, including tax reform, changes in the health care laws, deep cuts in many domestic programs and a major buildup of the military.



Related: 4 Political Minefields Waiting for Trump Following His Health Care Failure

“I would never rule out presidential successes in a Congress controlled by his party, even in the last year of Trump's term,” Larry Sabato, director of the University of Virginia’s Center for Politics, said Wednesday. “But this particular president is hobbled far more than most. His party is deeply divided into factions, and if Trump's unpopularity continues, GOP congressmen will be looking out for themselves as 2018 approaches. So, I'd say Trump's potential productive period is more like 18 months, and that estimate may be generous.”

The counterweight to that, of course, is that many House Republicans are in safe districts drawn by Republican-controlled state legislatures, and they will be tough to unseat. It’s more likely that in many of the races, the Republican primaries could be determinant, especially if there are a lot of challenges. Nathan L. Gonzales, a political analyst with Inside Elections, says the current “playing field” is far more favorable to the Republicans than the Democrats.

“But there are still 18 or 19 months before the election, and I think there is an opportunity for the playing field to change,” he said. “It changed pretty dramatically from 2009 to 2010 [in the GOP’s favor]. I think that’s sort of the scenarios Democrats are hoping for. Because fundamentally, mid-term elections are referendums on the president’s party. If people don’t like the president or the job he is doing, they can’t vote against him in 2018 – they would have to vote against members of his party.”

But Trump is not getting much help from his party. In the first few months of 2017, the House Republicans have not exactly made a strong case for voters to keep them in control of the chamber. The effort mounted by House leadership to repeal and replace the Affordable Care Act not only failed, but it also forced dozens of potentially vulnerable party members to support a bill that was so politically toxic that only 17 percent of Americans said they supported it.

Related: Looks Like Trump Won’t Be Getting Any Money to Build His Wall This Year

Trump’s biggest problem, for now, is that his job approval rating is at 41.8 percent, according to the Real Clear Politics average -- a bad omen for a newly installed president and one that could come back to haunt his party in the mid-terms. However, analysts warn against attaching too much significance to that in looking down the road.

“What’s much more important is his job approval rating in the 10 or 12 states where there’s going to be a top 10 Senate race or in key congressional districts where the majority is hanging in the balance,” Gonzales said.

Trump and the GOP may also have to deal with the demographic wave of millennial voters who now make up the largest single generational cohort in the US electorate, and are only gaining in numbers. Those younger voters did not turn out in strength last November, one of the factors that helped Trump win the election. However, those who did vote overwhelmingly for Democrat Hillary Clinton.

A candidate who can mobilize younger voters -- or more actions by Trump that independently push them to the polls, like his executive order eviscerating Obama-era environmental regulations -- could make November 2018 an even tougher month for the GOP.

While Trump’s approval rating will be important, more important is whether the GOP and Trump can show they can govern.

Related: Trump Takes Another Swing at Controversial Budget Cuts

Whit Ayres, a veteran Republican pollster and political analyst, said, “The Republicans have been given control of the entire federal government, and now they have to deliver on at least some of the basic promises they made to the American people. If they manage to get a pro-growth tax reform bill through; if they manage to get some sort of replacement for Obamacare through that helps to make health care more affordable; if they reform the regulatory environment that increases economic growth and brings back some manufacturing jobs. Then they are in a very, very strong position to hold on to both the House and the Senate.”

But even if Paul Ryan remains Speaker of the House in 2019, the Democrats wouldn’t have to gain many seats at all to make his fractious GOP conference all but unmanageable.

The hard-right wing of the party, embodied in the House Freedom caucus, already wields power disproportionate to its size because it controls enough votes to deprive Ryan of a majority on legislation its members oppose. Those aren’t the guys (they’re all guys) who will be at risk of losing seats to a Democrat in 2018. It’s the less doctrinaire members of the conference whose heads will be on the block.



The National Journal reports, “Of the 36 at-risk House Re­pub­lic­ans, ac­cord­ing to The Cook Polit­ic­al Re­port’s rat­ings, 28 rep­res­ent urb­an or sub­urb­an dis­tricts where Trump isn’t par­tic­u­larly pop­u­lar. And for every one of them Ryan loses, he needs to either placate the Freedom Caucus or cut a deal with Democrats.

Related: Why Another Government Shutdown Is Suddenly in the Cards

That means that many of Trump’s agenda items that are toxic to Democrats start to look less viable as pieces of legislation after 2018 -- and maybe a lot sooner if Trump’s unpopularity starts to make House Republicans worried about their election prospects.

Which brings us back to Trump’s timeline. He still has time before members of the House start thinking about their reelection races, and there is certainly the potential that a few legislative victories could create the momentum he needs to push much of his agenda through Congress. But if the Trump Train doesn’t start rolling soon, it may never really get under way at all.