A Democratic pollster warned Wednesday that the party is not motivating lower-propensity voters at the levels it needs, putting gains at risk with poor messaging.

“Democrats are setting themselves up to squander the opportunity Donald Trump is serving them on a silver platter because they aren’t motivating the Rising American Electorate to vote this fall,” said Page Gardner, the president of the Women’s Voices Women Vote Action Fund, which funded the poll.

The poll, conducted by Democracy Corps and Greenberg Research, finds the generic Democratic ballot advantage at a new high — 49 percent support for Democrats to 38 percent for Republicans. That marks a gain from November, when the WVWVAF, warned that the advantage had tumbled to just five points.

“Our prediction is that 40 million Americans who voted in 2016 won’t cast a ballot in the 2018 midterms — and to make matters worse, two-thirds of those drop-off voters will be members of the Rising American Electorate,” said spokesman Kevin McAlister at the time.

The new poll, conducted entirely after the passage of tax cuts that have grown more popular amid news of worker bonuses, found both Democratic recovery and risk. The gains, according to pollsters, came from working class white women who had cooled on President Trump. In late 2017, there was a surge of Republican support from those voters; the new poll found that advantage slipping from 18 to eight points.

The problem, according to WVWVAF, is a drop-off in enthusiasm among the “Rising American Electorate” — less white and much younger than the electorate that wins midterms for Republicans. Unmarried women dropped off slightly; other voters in the cohort were less enthused about the midterms, relative to Trump voters.

“Democrats are running out of time to prove themselves to the Rising American Electorate and make sure voters know they will disrupt Washington and knock Trump for not keeping his promises,” Gardner said. “It looks like the RAE is fed up and starting to tune out. If Democrats want to win, they need to prove themselves to the RAE so they are fed up and mobilized.”

The paradox: The pollsters’ preferred messaging sounds much like the messaging of House and Senate Democrats — messaging that Republicans believe was successful, if temporarily, in making the tax cuts unpopular. One version of the message: “Donald Trump is wedded to trickle-down economics and just gave huge tax cut taxes to big corporations and the richest. The Democrats say the richest must pay their fair share of taxes.”

Among Democrats, the debate over how to run in 2018 is fairly binary — whether to run on “kitchen table” issues or whether to run “against Trump.” One legacy of the party’s 2016 loss is a sense that Hillary Clinton gave up traditional Democratic advantages by running against Trump’s negatives while de-emphasizing policy — plentiful in her campaign materials but not in her ads.

According to WVWVAF, however, the party can’t separate the two messages — running against Trump, and running against Republican economics — without putting voters to sleep.