Former Cameron County District Clerk Eric Garza defeated longtime Cameron County Sheriff Omar Lucio in the Democratic Party primary runoff election Tuesday night.

Garza won 57% of more than 20,000 ballots cast during the primary runoff election, according to preliminary results published Tuesday night by the Cameron County Elections Department.

The results will remain unofficial until canvassed.

Tuesday marked the end of a contentious, monthslong campaign.

Garza, who served as district clerk from 2015 to 2019, and former San Benito police Chief Michael R. Galvan challenged Lucio in March, when Cameron County held the Democratic Party primary.

About 43.2% of voters supported Lucio, according to results published by the Elections Department. About 40.9% of voters supported Garza.

Galvan placed a distant third, with nearly 5.2% of the vote.

No candidate won more than 50% of ballots cast in the primary, sending the race to a runoff.

The coronavirus pandemic delayed the runoff election until July. In the meantime, the campaigns went negative.

Garza attacked Lucio in television ads, claiming that 17 people died at the Cameron County jail during the past decade "because of his mismanagement."

Lucio fired back, reminding voters what happened in 2001, when Conrado Cantu replaced him as sheriff.

After a federal investigation, which concluded that Cantu had been working with drug traffickers since the day he became sheriff, a grand jury indicted him. Cantu pleaded guilty to racketeering.

Lucio returned to the Sheriff's Office in 2005. Cantu went to prison.

In a campaign ad, Lucio suggested that drug traffickers wanted him to lose the runoff election.

"Who benefits if Omar Lucio is gone?" asked the campaign ad, which showed photos of drug cartel bosses, including former Gulf Cartel kingpin Osiel Cardenas Guillen and Sinaloa Cartel leader Joaquin "El Chapo" Guzman. "It happened in 2001."

Garza will face Republican candidate John Chambers — the former Indian Lake police chief — in November.