“Bernie or bust” is their rallying cry, and many supporters of socialist Sen. Bernie Sanders, I-Vt., say they will vote for President Trump if their candidate is denied the Democratic nomination a second time.

After the 2016 election, the Cooperative Congressional Election Study found about 12% of those who voted for Sanders in the Democratic primaries voted for Trump in the general election. There are early signs that Sanders fervor is so strong that this could double in 2020, a development that could hand the White House to Trump for a second term.

An Emerson College poll this month showed 26% of those who support Sanders in the Democratic primaries and caucuses would support Trump over Sen. Elizabeth Warren, D-Mass., despite their overlapping policy positions.

The Sanders-to-Trump inclination stems in part from the belief that the Democratic National Committee “cheated” Sanders in the bitter 2016 primary with the superdelegate system and Democratic staff bias in favor of eventual nominee Hillary Clinton. Concern over establishment control of the nomination process and other aspects of the campaign season persist among Sanders loyalists.

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“If they cheat again, I have told people I will vote for Trump,” Pennsylvania resident and Sanders supporter Keith Ward, 58, told the Washington Examiner. “Not because I like him, but because if this country is going down a slippery slope, they have no one to blame but themselves ... [no] matter how much damage I believe Trump is doing.”

Ward voted for Sanders in the 2016 Democratic primary and for Green Party candidate Jill Stein in the general election. “I felt I had no choice,” he said, adding that he felt his 2016 vote would send a message. “I'm just not sure the [Democratic] Party heard it.”

Another Sanders supporter expressed a similar sentiment: “If the DNC screws him again, like it's already looking they will, I'll stay home on voting day. Hell, I may vote for Trump just to make sure their candidate loses.”

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The Trump presidency adds a layer of complication to the "Bernie or bust" mentality.

“We have the ultimate swamp monster in the White House,” Stephen, a 39-year-old Sanders supporter from Massachusetts, told the Washington Examiner. While he said it will be hard to cave to the Democratic Party establishment if it “doesn’t play fair” and Sanders doesn’t win the nomination, he will probably do what Sanders recommends and vote for the Democratic ticket if he thinks the candidate can defeat Trump.

But Democrats' fear of Trump also serves as leverage for Sanders loyalists. By threatening to vote against a moderate or establishment candidate, or to not vote at all, “Bernie or bust” could push candidates leftward.

A 41-year-old Sanders supporter who is a nurse and lives outside Charlotte, N.C., said that if Sanders loses, his vote in the 2020 general election would depend on the Democratic nominee, if he votes at all. He would vote for Warren or Hawaii Rep. Tulsi Gabbard, but former Vice President Joe Biden, New Jersey Sen. Cory Booker, and California Sen. Kamala Harris are among those on his “no” list.

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“Maybe we'd be in a better position to reform government in 2024 after four more years of Trump than we would under a Democrat who will lull us to sleep with charisma while bombing thousands of people abroad and doing nothing to help the working class,” he told the Washington Examiner.

Brian Schaffner, a Newhouse professor of civic studies at Tufts University who worked on the Cooperative Congressional Election Study, cautioned that the sample size for the 26% figure in the Emerson poll is small.

Only about 103 people in the poll said they supported Sanders, and its margin of error is 5.2%. Other state-level Emerson polls showed single-digit percentages of Sanders supporters choosing Trump over Warren.

“I wouldn't take their claims that they would vote for Trump over Warren too seriously,” Schaffner told the Washington Examiner. “It is more likely just a way of them signaling to the pollsters who are asking them that they really want Bernie (and not somebody else) to win the nomination.”