Democrats smell blood in the water. The Trump administration is on the ropes. Republicans in Congress can’t seem to mover their agenda forward. And the Democratic base is fired up like never before.

Across the country, enthusiastic progressives, many young and inexperienced, are announcing their intentions to run for office. Democratic organizations are actively recruiting people and training sessions for first-time candidates abound. Talk of a 2018 wave, though premature, permeates twitter feeds and cable news shows.

The excitement may well be justified. Even conservatives are abandoning Trump and speculating on how his presidency ends. Support for the GOP Obamacare repeal bill is tanking. There’s doubt that the GOP can push much of an agenda because of the distraction of the Trump investigations. Together, these factors will likely depress Republican turnout in the midterms and sour independents on the party.

However, Democrats should keep in mind that the forces propelling them are reactionary. There’s no evidence of any broad support for a progressive agenda right now. There’s just evidence of rejection of Trump and Republican incompetence. The same forces that thrust Trump into the White House are still in play and will be until one party or the other addresses their concerns.

A recent study shows that Clinton lost a large number of voters to Trump who supported Obama in 2012. Those are change voters who long for a different outcome from our political system. They might vote for change again next year, but if Democrats win and don’t deliver, they’ll throw them out, too.

Democrats need to give voters something to vote for, not just against. They should take a page out of the Bernie Sanders playbook and embrace a message of economic populism that crosses racial and ethnic lines to appeal to working class voters. Add a little optimism to the outrage and give people hope for the future.

Another study says that cultural, not economic, anxiety propelled Trump’s supporters. That may be true but that cultural anxiety includes a lot of factors that include a form of economic insecurity. Too many progressives want to interpret it as only racism, xenophobia and homophobia, but it’s just as much a fear of the loss of a way of life.

People of all races and creeds in small towns and cities across the Midwest and places like North Carolina are watching the institutions that sustained them disappear. Church attendance is dropping. The merchant class has been replaced by big box stores. Civic organizations like Rotary and Civitan Clubs are shrinking. The fabric that held these communities together for a hundred years is disintegrating.

Democrats need to recognize their struggles and look for answers in either new institutions or ways to revive old ones. If they don’t, working class African-Americans will stay home again. Many white working class voters will still be susceptible to politicians playing on their fears and continue to vote for demagogues who make promises they can’t keep.

Democrats and progressives may well have a wave to ride in 2018. They need to tap into more than just the anger, frustration and resentment that propels it, though. They need to return to their roots and once again be the party of working Americans, standing up against concentrations of wealth and industries that become too big to fail. Otherwise, the wave they’re trying to catch in 18 months will sweep them out to sea again in 2020 like they’ve done to both parties every two to four years for the past decade.