Pete Buttigieg shoots to the top of the 2020 field in Iowa poll

Jeanine Santucci | USA TODAY

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WASHINGTON — The 2020 Democratic field in Iowa is led by four candidates for president, with South Bend, Indiana, Mayor Pete Buttigieg gaining ground in the last few months, according to a poll released Tuesday.

The Monmouth University poll found that Buttigieg is the favored candidate of 22% of respondents, putting him in the lead for the first time in Iowa. Former Vice President Joe Biden was backed by 19%, Massachusetts Sen. Elizabeth Warren by 18% and Vermont Sen. Bernie Sanders by 13%. All other Democratic candidates received single-digit support in the survey.

But, the survey results suggest that the race is still fluid; less than one-third of respondents said they are firmly set on their choice.

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Buttigieg's support has grown since Monmouth's August survey, where he was at 8%. Biden, meanwhile, has ticked down since the summer, when he was the pick of 26% of Monmouth respondents.

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The Monmouth survey's margin of error was plus or minus 4.6 percentage points. The results are based on results among 451 Iowans likely to participate in the state's Democratic caucus.

Monmouth also asked respondents about former New York City Mayor Mike Bloomberg, who has recently signaled intentions to run. He was the top pick of a single voter out of 361 surveyed after he was added to the lineup, and when asked about his favorability, he came out with a net negative 31 points.

Monmouth University Polling Institute Director Patrick Murray said that when voting begins in February, voters are more likely to turn a candidate that has been in the field longer if the race still seems wide open.

"It makes more sense to pay attention to someone like Amy Klobuchar in this scenario than look for a white knight to come riding to the rescue," Murray said. Klobuchar stood at 5% in this poll.

Buttigieg has recently performed well in early state polling. A Quinnipiac poll in New Hampshire had the Democratic hopeful with 15% of support, within striking distance of Biden at 20% and Warren at 16%. Sanders stood at 14%.

A recent USA TODAY/Suffolk University poll conducted nationally also found him holding his own against Biden, Warren and Sanders.

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