Former Vice President Joe Biden's hypothesis that most Democrats fall closer to the middle of the political spectrum is flawed, according to one researcher.

A majority of Democrats want the party to adopt more liberal, progressive policies and candidates than more moderate, centrist ones, Lord Michael Ashcroft, a polling expert, former deputy chairman of the United Kingdom's Tory Party, and a conservative donor, wrote in his book Half-Time: American Public Opinion Midway Through Trump’s (First?) Term.

Ashcroft's research found 57% of Democrats prefer liberal candidates, while 28% seek a more moderate option. The trend is the result of tectonic shift within "the Democrat Core" into which a third of the population fell in 2016.

"Two of these groups (the 'Mainstream Liberals' and the more working-class and socially conservative 'Blue-Collar Democrats') have shrunk, while the 'Cosmopolitan Activists,' by far the most progressive and politically active of the segments, have more than doubled in size," Ashcroft wrote of the group that is predominantly young, female, white, college educated, and earning more than $150,000 a year. "Cosmopolitan Activists are by far the most likely to share political information on social media, donate to campaigns, attend political meetings, and campaign actively for candidates."

One Iowa caucusgoer told Ashcroft and his team, " The Democrats are far too moderate, at least for a lot of the younger crowd."

"Some argued the party should be willing to talk about socialism ... and that someone like Joe Biden — whom many older participants said they hoped would decide to run — 'isn't necessarily change,'" Ashcroft said.

Ashcroft's study, based on a series of focus groups and surveys of 30,000 and 15,000 respondents conducted between the fall of 2016 and shortly after the 2018 midterm elections, was published earlier this year. The international businessman, author, and philanthropist determined the top two qualities Democrats seek in a 2020 nominee. A preferred candidate is someone "who will keep a civil, courteous tone even when they are attacked" and "who will fight for Democratic principles and positions rather than compromise," the book says.

Ashcroft's work conflicts with Biden's rationale for entering the 2020 race for the presidency.

“If you look at all the polling data and look at the actual results, the party has not moved," Biden told reporters after a union event earlier this month. "The fact of the matter is the vast majority of members of the Democratic Party are still basically liberal-to-moderate Democrats in the traditional sense.”

"Show me the really left-left-left-left-wingers who beat a Republican, a Republican. So the idea that the Democratic Party is sort of stood on its head, I don't get," Biden said.

Biden, who has not declared a White House bid, records an approximate 9 percentage-point advantage over his closest potential rival, Sen. Bernie Sanders, according to the latest polling average from RealClearPolitics. Other more moderate contenders include Sen. Amy Klobuchar of Minnesota and former Rep. John Delaney of Maryland.