(CNN) A unique voting group from the 2016 election -- voters who backed independent Vermont Sen. Bernie Sanders but were willing to vote for Donald Trump -- seems to be non-existent in the early days of the latest presidential contest.

Trump's June 2015 entrance into the presidential election quickly turned that race from a debate over candidates' ideology into a question of whether voters wanted a political insider or outsider as the successor to President Barack Obama.

Perhaps no group of voters signified that debate more than those who preferred Sanders (a progressive independent who was seen at the time as further left than the mainstream Democratic Party) but were willing to vote for Trump (a billionaire espousing conservative positions who took over the Republican Party with his bellicose rhetoric and take-no-prisoners political style). Those who wanted to link Trump -- with his promise to "drain the swamp" and anti-elite message -- and Sanders often called them "populists" and "anti-establishment."

Polling before the 2016 election showed a crossover between those who preferred Sanders but would be willing to vote for Trump. A May 2016 poll, during one of the more heated portions of the Democratic primary between Hillary Clinton and Sanders, from ABC and Washington Post found 20% of Sanders voters also supported Trump

Clinton was later able to consolidate Democratic support behind her -- another ABC/Washington Post poll released days before November 2016's vote showed 8% of former Sanders supporters planned to vote for Trump in that election.

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