It's become a cliché that each faction within each party believes that victory would be assured if only the party would follow their preferred policy approach. Democrats in the Congressional Progressive Caucus, which has been becoming increasingly involved in primaries across the country in a way it hasn’t before, now has polling to back up its claim.

The data, crunched by Democratic pollster Celinda Lake, comes from a survey of 600 likely 2018 voters over the phone in 30 targeted swing districts, and an additional over sample of 300 Democratic-leaning surge voters. (Those are people who don’t have a history of voting and are less certain to vote in 2018.)

Swing districts often have a roughly equal balance of Democrats and Republicans, leading political strategists to advise moderation as the path to victory. But, Lake’s poll found, that’s not what voters in those districts actually want.

Almost three-quarters of the voters surveyed, for instance, supported “Medicare for All.” Policies dealing with cheaper prescription drugs, infrastructure, protecting Social Security and Medicare, and cracking down on Wall Street, are exceedingly popular with swing and surge voters alike, the survey found.

Lake’s memo claims, “These policies not only motivate the progressive base, but make voters more likely to support Democrats. A majority of voters (52 percent) said they would be more likely to vote for a candidate talking about the progressive policies we mentioned, while only 26 percent would be less likely.”

Rep. Pramila Jayapal, D-Wash., said that that the poll shows Democrats “can have that blue tsunami,” not just a blue wave, if they lean into progressive policies and messaging. The results show enthusiastic support for progressive policies in 30 swing districts, mostly held by Republican incumbents. “Our polling shows running as a bold progressive is a political winner,” Jayapal, vice chair of CPC, said on a press call.

Progressive legislative priorities ranked high across districts, but the memo also found progressive messaging resonates with voters. Jayapal noted that even though Democrats want to generate turnout among surge voters without alienating swing voters, the data shows the same messaging works with both groups of people.

A majority of the voters surveyed preferred a bold economic vision, as opposed to an incremental approach. When asked, 52 percent said they prefer “a bold and comprehensive agenda to rewrite the rules of the economy,” compared to the 36 percent of voters who would choose to “make our economy work for everyone by building on the success of the past.”

Another takeaway from the memo, Jayapal said, is that talking about race is not something Democrats “should shy away from.” Support for a policy to “improve opportunity for working and low-income families - white, black, and brown - by investing $2 trillion in rebuilding our roads, bridges, schools, and communities, while creating millions of good-paying jobs” had more support among likely voters than the phrasing of the policy that did not include race.

Progressive candidates that win elections are seen as a niche group that “somehow managed to beat the odds,” despite polls showing that progressive policies are actually mainstream values to voters across the country, Rep. Raúl Grijalva, D-Ariz., said.

The CPC memo comes in the wake of an upset victory by Democrat Conor Lamb in deeply conservative western Pennsylvania. Lamb has been caricatured as a conservative, because of his embrace of gun culture and personal opposition to abortion. But politically he was pro-choice, supporting the legal right to an abortion, and ran against corruption in Washington. He pushed for more investment in infrastructure, a robust response to the heroin epidemic that includes legal moves against “drug company boardrooms,” as well as action to lower health care costs, protect Social Security and Medicare, and lessen the burden of student loans.

This commentary was originally published by The Intercept