Former US Vice President Joe Biden still leads the Democratic pack of presidential contenders in a poll of Iowa voters, with Bernie Sanders, Elizabeth Warren and Pete Buttigieg in a tight battle for second place.
Mr Biden is the first choice of 24 percent 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.
Mr Sanders, a US senator, is the first choice for 16 percent of respondents, while Ms Warren, also a US senator, and Mr Buttigieg, the mayor of South Bend, Indiana, are at 15 percent and 14 percent, respectively. No other candidate managed double-digits.
Senator Kamala Harris registered 2 percent and senator Amy Klobuchar and former Texas congressman Beto O'Rourke are both at 2 percent. Seven candidates registered 1 percent.
"We're starting to see the people who are planning to caucus start to solidify," said J. Ann Selzer, president of Des Moines-based Selzer & Co, which conducted the poll.
"There's a lot more commitment than we normally see this early. And some of these candidates who've been under the radar start to surface and compete with Joe Biden."
She said many candidates in the large field had failed to make a breakthrough. Nine did not register support in the poll.
"There's always been a question mark as to how many can get any real traction," Ms Selzer 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 18 June. Mr Biden has been the consistent leader in most national and state polls since he first entered the race in late April. Mr Sanders runs second to Mr Biden in most polls.
A spokesperson from 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 planned to attend a caucus in person and those who would participate in a virtual caucus online or by phone.
That makes the results of this poll not directly comparable to past polls of the presidential field, the Register said. Mr Biden also led in the last poll in March, with Sanders in second. Ms Warren and Ms Harris were in third and fourth place in March, and Mr Buttigieg was largely unknown.
The poll said Mr Biden showed a sign of potential weakness, with only 29 percent of those who listed him as their first choice saying they were "extremely enthusiastic." The number is substantially higher, 39 percent, 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 five-minute speeches by 19 Democratic candidates.