“There are definitely persuadable voters out there and the question we should be asking right now is: ‘Who can be persuaded to embrace our vision of the future?’” report co-author Lanae Erickson Hatalsky of Third Way said in an interview. “The idea that there was this rising electorate that would automatically deliver progressive victories wooed us away from doing the hard work of trying to find common ground with people since it seemed easier to just find people who agreed with us.”

Erickson Hatalsky argues that voting trends suggest that some voters swing back and forth between the two parties rather than remain consistently loyal to one party or the other. For example, hundreds of counties across the United States flipped from voting for Barack Obama in the 2012 presidential election to voting for Trump in 2016. Some congressional districts also delivered victory for Trump while at the same time reelecting Democratic members of Congress, like Cheri Bustos in Illinois and Matt Cartwright in Pennsylvania.

“There are clearly people out there who have not decided that they vote for only one party,” Erickson Hatalsky said. “I think that’s hopeful because it indicates that if the Democratic Party takes the time to listen to what it is that these people are looking for, we may be able to expand our coalition.”

The report notes that there has been a rise in the number of voters who identify as independent in recent years, and suggests that they could be a potential target for the Democratic Party. Some political scientists, however, maintain that independent voters are really partisans in disguise—people who may not want to publicly identify as a Republican or a Democrat, but nevertheless consistently vote for candidates of a particular party. Third Way has challenged this conclusion, and does so in the report by tracking how independents have swung as a voting bloc back-and-forth between voting for Democrats to Republicans in presidential elections dating back to 1976.

“Independents lean toward one party or another, and vote for that party, over shorter time horizons, but this trend shows that over longer time horizons partisan loyalties are not fixed in place for independent voters,” Erickson Hatalsky said.

But what if there isn’t a significant number of voters available for Democrats to win over or win back? What if, instead, the partisan battle lines are now firmly entrenched, and spending time, energy, and effort trying to change hearts and minds proves to be a losing proposition for the party?

Alan Abramowitz, a political scientist at Emory University, is skeptical that Democrats can significantly grow their base by converting large numbers of either Republicans or Trump voters. He believes Democrats would be more effective if they focused on increasing turnout of core Democratic constituencies, such as African American, Hispanic, and younger voters.