St. Paul DFLers endorsed incumbent City Council member Dai Thao on Sunday, after his two challengers walked out of the convention in protest.

Thao, who was first elected in 2013 and represents St. Paul's First Ward, secured the DFL endorsement with more than 70% of delegate votes. To win the endorsement — a crucial stamp of approval in St. Paul — candidates must win at least 60% of the vote.

"We worked hard all year building our delegate base, and so we're proud of the amount of delegates that we turned out," Thao said in an interview Monday. "It's helpful when you've been in office and been working and serving the community."

The endorsement was an affirmation for Thao, who a year ago was facing misdemeanor charges over an episode of alleged voter misconduct during his failed run for mayor. His supporters remained steadfast, and in November, a Ramsey County judge found him not guilty.

The two candidates challenging Thao for the DFL endorsement — Liz De La Torre and Anika Bowie — issued a joint statement Monday saying they were disappointed by the convention's outcome.

"We did everything we could to participate fully in the process and abide by the endorsement," the statement said. "However, it became clear that the process was not fair, transparent or equitable."

In an e-mail, Bowie said the St. Paul DFL "did not protect the integrity of the process and did not excuse campaign staff who violated rules on multiple occasions." Both Bowie and De La Torre plan to file a complaint to challenge the endorsement, she said.

Thao said Monday that he was unsure why Bowie and De La Torre left the convention.

About 300 people attended the convention, said Ward One DFL co-coordinator Matt Hill. Bowie and De La Torre walked out — and asked their delegates to leave, too — after Thao narrowly missed winning the endorsement on the first ballot, Hill said. Thao won on the second ballot, earning 74% of delegate votes.

In a Facebook post, convention chairman Chuck Repke said there were challenges distributing the first ballot because two precincts with "a significant delegation" of nonnative English speakers "appeared to have commingled in their seating."

"With great effort from the translators and party officers it was finally sorted out and the ballot was turned in," he said.

In a joint statement, Hill and city DFL co-chairs Beth Commers and Garrison McMurtrey said the St. Paul DFL "strives to create an inclusive and welcoming process in all its activities, including endorsements."

"All campaigns in Ward One were provided with the same tools and resources to seek this endorsement," the statement said.

All seven City Council seats are up for election this year.

The DFL held a convention for the open Sixth Ward seat on Saturday, but of the four candidates who sought the endorsement — Nelsie Yang, Terri Thao, Tony Her and Alexander Bourne — none garnered enough votes to secure it.