The civil war in the Democratic Party is heating up, with mainstream party members growing increasingly alarmed as fiery leftist Bernie Sanders takes the lead in the presidential nominating contest.

“Every day, I worry about Bernie Sanders being the nominee,” Rhode Island Gov. Gina Raimondo told Yahoo Finance recently. “I don’t think he can beat President Trump. Socialism isn’t the answer. The American people, I think, will reject that in November.”

A new Quinniac poll shows for the first time that Sanders has become the leading Democrat nationwide, with 25% of Democratic voters saying he’s their choice. Joe Biden, the frontrunner until recently, dropped from 26% to 17%. Mike Bloomberg has soared into third place, with 15% of the Democratic vote, followed by Elizabeth Warren (14%), Pete Buttigieg (10%) and Amy Klobuchar (4%).

Buttigieg slightly edged Sanders in the fouled-up Iowa caucus, but Sanders is on track to win the New Hampshire primary on Feb. 11. Biden’s campaign is flatlining at precisely the wrong time. Biden’s bid isn’t dead yet, but it probably will be if he can’t win in Nevada or South Carolina, the next states to vote after New Hampshire.

[Check out our full interview with Gov. Gina Raimondo of Rhode Island.]

Bloomberg was an afterthought when he entered the race in November, and it’s still hard to see how he could win enough delegates to clinch the Democratic nomination outright. Polling site fivethirtyeight gives Bloomberg less than a 1% chance of winning a majority of delegates in the primaries and clinching the nomination that way. Sanders? A 50% chance of winning enough delegates.

But Bloomberg had something else in mind when he decided to run: An indecisive Democratic primary season that produces no winner and elevates a leftist such as Sanders. If that happens, it would lead to a tumultuous “brokered convention” over the summer in which the Democratic delegates wheel and deal to decide who the nominee is. In that scenario, it’s possible they could pick Bloomberg, if he does reasonably well in the primaries.

‘His message is resonating’

Polls show that Sanders would beat Trump in a one-on-one general election matchup, by an average of 4.3 percentage points. But many Democrats don’t buy that. Trump would have months to savage Sanders as a socialist and lampoon his something-for-everybody policies. He’d doubtless play up the trillions of dollars in tax hikes Sanders proposes.

“His message is resonating,” Raimondo acknowledges. “People are angry. We can’t tell them they shouldn't be. We have to tell them we have a better solution than his solution.”