Pete Buttigieg took a narrow lead in the first batch of long-delayed results from the chaotic Iowa Democratic Party caucuses on Tuesday.
But Reuters reports former Vice President Joe Biden trailed badly in fourth place with about 62% of precincts reporting.
US Senator Bernie Sanders was a close second place and US Senator Elizabeth Warren placed third in the first results.
The results were released nearly 21 hours after Iowans poured into more than 1,600 public locations to caucus.