Democratic Rep. Keith Ellison, the first Muslim elected to Congress and a top official with the Democratic National Committee, filed to run for Minnesota attorney general Tuesday, saying he wanted to join the legal fight against President Donald Trump.

A sixth-term lawmaker widely regarded as among the most liberal members of Congress, Ellison had been eyeing statewide office in Minnesota for months. He considered running for the Senate seat vacated by former Sen. Al Franken before backing Gov. Mark Dayton's appointee, Sen. Tina Smith. And he weighed a run for attorney general until Lori Swanson, the current officeholder, decided to run for a fourth term this winter.

But Swanson changed course Monday, launching a late bid for Minnesota governor. Ellison and others pounced, filing for the office on Tuesday.

"It was attorneys general who led the fight against the Muslim ban," Ellison said after filing to run for the office, referring to Trump's ban on travel to the U.S. by visitors from several Muslim-majority countries. "I want to be a part of that fight."

Among the Democrats rushing to succeed Ellison in his liberal Minneapolis congressional district was state Rep. Ilhan Omar, the first Somali-American Muslim elected to a state legislature in the U.S.

Ellison's first statewide campaign will likely be far more challenging than his congressional runs. He represents a solidly Democratic district in Minneapolis and some surrounding suburbs and has never faced a major challenger since first being elected to Congress in 2006. But outside the cities of Minneapolis and St. Paul, Minnesota is more conservative and could be less receptive to his confrontational approach.

Ellison co-chaired the House's Congressional Progressive Caucus from 2011 to 2017 and recently assumed the charge of pushing to expand a Medicare-for-all, single-payer health care program. He has also served as deputy chairman of the Democratic National Committee since 2017, after losing the race for its top job to Tom Perez. Both Ellison and the DNC said he would keep his spot as deputy chairman.

By entering the race for attorney general, Ellison is taking on the state party's endorsed candidate as well as longtime Democratic state lawmaker and former Minnesota Attorney General Mike Hatch. All filed for the office Tuesday.

Several Minnesota Democrats immediately joined the race for the U.S. House seat Ellison holds. State Sen. Patricia Torres Ray, a prominent voice on Hispanic issues, filed less than an hour after Ellison filed for attorney general. Former state House Speaker Margaret Anderson Kelliher also jumped in.

Omar was elected in 2016 and said at the time that she considered her election to be a "counter-narrative" to then-President-elect Trump.

Omar immigrated to the U.S. when she was 12, after her family fled war-torn Somalia and spent four years in a Kenyan refugee camp. Her story is a familiar one in Minnesota, which is home to the largest Somali population in the United States. While other Somali-Americans have been elected to school boards and the Minneapolis City Council, she was the first to be elected as state lawmaker.

Ellison said he wouldn't endorse a successor.

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