Biden is still leading in a 2020 Iowa poll, while Sanders, Warren, and Buttigieg are fighting for second place

Reuters/Jonathan Ernst

U.S. Democratic presidential candidate former Vice President Joe Biden holds a campaign stop in Des Moines, Iowa, U.S. May 1, 2019.

• Former Vice President Joe Biden still leads the Democratic pack of presidential contenders in a poll of Iowa voters released on Saturday.
• Bernie Sanders, Elizabeth Warren and Pete Buttigieg are in a tight battle for second place.
• Sen. Kamala Harris registered 7%, and Sen. Amy Klobuchar and former Texas Rep. Beto O'Rourke are both at 2%. Seven candidates registered 1%.
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Former Vice President Joe Biden still leads the Democratic pack of presidential contenders in a poll of Iowa voters released on Saturday, with Bernie Sanders, Elizabeth Warren and Pete Buttigieg in a tight battle for second place.

Biden is the first choice of 24% of likely Democratic caucus-goers in Iowa, the state that kicks off the presidential nominating race next February, in the Des Moines Register/CNN/Mediacom Iowa Poll.

Sanders, a senator, is the first choice for 16% of respondents, while Warren, also a senator, and Buttigieg, the mayor of South Bend, Indiana, are at 15% and 14%, respectively. No other candidate managed double-digits.

Sen. Kamala Harris registered 7%, and Sen. Amy Klobuchar and former Texas Rep. Beto O'Rourke are both at 2%. Seven candidates registered 1%.

Reuters/Rachel Mummey

Democratic 2020 presidential candidate Elizabeth Warren makes one of a series of local visits in Fairfield, Iowa, U.S. May 26, 2019. Picture taken May 26, 2019.

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O'Rourke addressed the poll results on Saturday, telling Yahoo News his low numbers wouldn't affect his campaign strategy.

"There is a lot of time before the Iowa caucuses. We've never been guided by a poll before," he said.

The Register's Iowa poll has a long track record of relative accuracy in the state.

More than 20 Democrats are vying for the right to challenge Republican President Donald Trump, who will formally launch his re-election bid on June 18. Biden has been the consistent leader in most national and state polls since he first entered the race in late April. Sanders runs second to Biden in most polls.

The Register said the poll methodology changed from its last few surveys. As a result of new caucus rules, the poll this time included a blend of those who plan to attend a caucus in person and those who will participate in a virtual caucus online or by phone.

Reuters/Brian C. Frank

Democratic 2020 U.S. presidential candidate Mayor Pete Buttigieg, who is gay and married to another man, addresses the Capital Pride LGBTQ celebration at the Iowa State Capitol in Des Moines, Iowa, U.S. June 8, 2019

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That makes the results of this poll not directly comparable to past polls of the presidential field, the Register said. Biden also led in the last poll in March, with Sanders in second. Warren and Harris were in third and fourth place in March, and Buttigieg was largely unknown.

Buttigieg celebrated his rising numbers on Saturday, telling The New York Times that the poll results show that "campaigning works."

"We've invested a lot of time and a lot of effort, not just nationally but getting to be known in Iowa, and obviously that's led to some growth."

The poll said Biden showed a sign of potential weakness, with only 29% of those who listed him as their first choice saying they were "extremely enthusiastic." The number is substantially higher, 39%, among all those who list another candidate as their first choice.

The Iowa poll was released on the eve of the biggest gathering of the Democratic race so far, an Iowa state party dinner in Cedar Rapids that will feature 5-minute speeches by 19 Democratic candidates.

The poll was conducted between June 2 and 5, with a margin of error of plus or minus 4 percentage points.

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