Sen. Elizabeth Warren is the top choice among likely Iowa Democratic caucusgoers, an Iowa State poll released Thursday found.

Warren has the support of 28 percent of likely caucusgoers, followed by Mayor Pete Buttigieg with 20 percent, Sen. Bernie Sanders with 18 percent, former Vice President Joe Biden with 12 percent, Sen. Amy Klobuchar with four percent, Sen. Kamala Harris with three percent and businessman Tom Steyer also at three percent. All other candidates are polling two percent or lower.

Rep. Tim Ryan, who dropped out of the race for president Thursday, had the support of zero percent of those polled.

This is the second round of polls Iowa State is conducting. The polls will be conducted monthly through late January. The poll is organized by Dave Peterson, professor of political science.

“Buttigieg being in second is probably the [most newsworthy] thing in there,” Peterson said. “Warren’s lead is up, and so she’s up to 28 percent, which is even higher than she was last month.”

Warren is up four percent from the September poll Iowa State conducted. Buttigieg is up seven percent, Sanders is up two percent and Biden is down four percent.

“Biden is way down to 12 percent, so Biden in fourth is an unusual result,” Peterson said. “In particular, he seems to be hemorrhaging his support.”

The gains for Buttigieg seen in the Iowa State poll follow other recent surveys showing Buttigieg performing stronger in Iowa than he does nationally.

A Quinnipiac University national poll of likely Democratic primary voters also released Thursday found Buttigieg with 10 percent support nationally.

Caucus night is 101 days away, leaving plenty of time for voters’ allegiances to shift and candidates’ positions in the horserace to change. The race today is different from where it was at the beginning of the summer, Peterson said.

“There’s some real shifts going on,” Peterson said. “If we look at the race — how it was four months ago — the narrative four months ago was ‘it’s Biden and Sanders’ and that does not seem to be the case right now. Warren and Buttigieg seem to be having a real surge.”

The survey of 598 likely Iowa Democratic caucusgoers was conducted by Civiqs for Iowa State from Oct. 18 to Oct. 22 and has a margin of error of plus or minus five percent at the 95 percent confidence level.