DES MOINES, Iowa — Pete Buttigieg held a slight lead over Bernie Sanders in the opening contest of the Democratic race for the presidential nomination, according to partial results released by the Iowa Democratic Party.

The results that came out Tuesday and Wednesday followed a period of caucus chaos. Technical problems marred the complicated process, forcing state officials to apologize and raising questions about Iowa’s traditional place atop the presidential primary calendar.

It was too early to call a winner based on the initial results from Monday’s caucuses, but Massachusetts Sen. Elizabeth Warren, former Vice President Joe Biden and Minnesota Sen. Amy Klobuchar were trailing in the tally of State Delegate Equivalents, according to the data.

The results reflected 75 percent of precincts in the state.

The two early leaders — Buttigieg, the former mayor of South Bend, Indiana, and Vermont Sen, Sanders — were separated by 40 years in age, conflicting ideology and more.

Sanders, a 78-year-old self-described democratic socialist, has been a progressive powerhouse for decades. For the 38-year-old Buttigieg, his early standing cemented his transformation from a little-known city leader to a legitimate force in the 2020 contest. Buttigieg is also the first openly gay candidate to earn presidential primary delegates.

“We don’t know all of the numbers, but we know this much: A campaign that started a year ago with four staff members, no name recognition, no money, just a big idea — a campaign that some said should have no business even making this attempt — has taken its place at the front of this race,” Buttigieg, said as he campaigned in next-up New Hampshire with his husband looking on.

Buttigieg’s early rise was rivaled for possible importance by the struggle of another moderate, Biden.