Democrats used a message built on health care and criticizing Donald Trump’s brash approach to the presidency to take back the House, but experts say that won’t be enough to defeat the president in 2020.

“This election is about health care,” House Minority Leader Nancy Pelosi, D-Calif., who could be speaker come January, said Tuesday at a news conference alongside Democratic House Campaign Committee chairman Ben Ray Luján that amounted to her closing pitch to voters.

Former President Barack Obama hit the midterm campaign trail harder than any other recently out-of-office chief executive in the modern era. At a campaign rally Friday in Miami, Obama urged voters to reject Republican “lies” and lit into Trump over his alleged plans to try unilaterally to end co-called “birthright citizenship,” which a constitutional amendment and a existing statute require be given to any infant born on American soil.

“A president doesn’t get to decide on his own who’s an American and who’s not,” Obama said. “That’s not how the Constitution works.”

Former Vice President Joe Biden used his stumping for Democratic candidates as a seeming test drive of anti-Trump messages for a possible 2020 White House bid. Some analysts believe Biden, of the Democrats currently eying a run, is the one best-positioned to defeat the incumbent president who remains extremely popular with his conservative base.

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On the trail, Biden has focused on what he describes as Trump’s fear-mongering, which the president denies employing.

“Three times this past week the forces of hate have terrorized our fellow Americans for their political beliefs, the color of their skin or their religion,” Biden told a rally crowd recently in Madison, Wis. “When that hate is given space to fester, it encourages other seamier parts of society to rear their ugly heads.”

And former Obama-era Attorney General Eric Holder, another potential 2020 candidate, has caught flak from Trump and conservatives for his edgy version of former first lady Michelle Obama’s “when they go low, we go high” message.

“When they go low, we kick them,” Holder said during an October campaign event.

But for Democrats, will it be enough in two years to challenge Trump and Republicans on their desire to take back the House and try again to dismantle the remaining parts of Obama’s 2010 health law while also focusing on the harsh rhetoric he uses to fire up his base?

“For right now, I think it was enough to run not only on the idea the GOP wanted to take away people’s health care, along with healthy dose of healthy anti-Trump rhetoric. That was enough to get us over the goal line,” said James Manley, a Democratic strategist. “But that won’t suffice in 2020.”

“Democrats are going to have to coalesce around a broader message,” he said, pointing to Democrats’ 2019 legislative agenda-building as the start of the messaging process.

“It has to include a unified pledge to try and improve the economy for middle class voters, and, yes, it will have to have a large splash of anti-Trump rhetoric.”

Marc Hetherington, a political science professor at the University of North Carolina, said there is one issue the president will try to make the foundation of his re-election bid — and, by extension, the central tenant of Republican congressional candidates’ campaigns: Immigration. That’s just what he did in the midterm cycle.

But Democrats should not bite, he said.

“It is hard to tell whether Democrats have found the right message for 2020 yet. The 2018 election was dominated by Donald Trump, specifically, and his signature issue — immigration,” Hetherington said. “It was striking to me that Democrats really didn’t engage Trump on immigration no matter how outlandish the claims he made were. It was more important to them to focus on anything else, regardless of how fast and loose Trump was with the facts.”

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Michael Steel, a former adviser to GOP Speaker John A. Boehner and Jeb Bush’s 2016 presidential bid, said “we’re a long way from knowing whether Washington Democrats have found a winning message for 2020.”

“Running against congressional Republicans is very different from running against Trump,” he said. “And, with a cast of thousands joining the Democratic field, it’s going to be quite a while before they turn from internecine battles to messaging for the general election.”

There’s one other issue on which Democrats cannot solely focus come 2020, experts said: Trump.

“What Democrats need to do to be successful is focus on old-style New Deal issues,” Hetherington said. “If the 2020 election turns on identity as was the case in 2016, that is not good news for Democrats.”

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