Hawaii state Sen. Kai Kahele officially announced Monday that he plans to run for the congressional seat occupied by U.S. Rep. Tulsi Gabbard, setting up a potential 2020 Democratic primary challenge for Gabbard early on as she embarks on her bid for president. The congressional seat represents the neighbor islands and rural Oahu.

Kahele made his announcement at the Mo‘oheau Bandstand in downtown Hilo, where Hawaii’s Democratic Party rallies every election. He was surrounded by his family, including his wife and two children, and supporters. Former state Sen. Brickwood Galuteria moderated the event. State Sen. Lorraine Inouye (D, Kaupulehu-­Waimea-North Hilo) also attended.

Announcing on Martin Luther King Jr. Day, Kahele referenced the late leader of the civil rights movement’s dedication to social and economic justice as inspiration for his congressional run, quoting King: “Life’s most persistent and urgent question is, What are you doing for others?”

Kahele said that the day was also significant for him because it was on this day three years ago that he found his father, the late state Sen. Gil Kahele (D, Hilo), at home having a heart attack.

“Nothing ever prepares a son or daughter for that moment, but I realized my dad needed medical attention immediately. As we quickly left the house for the hospital, it never occurred to me, or my dad, or my mom, that as we raced out of the driveway, this would be the last time he would leave our family home, never to return again,” said Kahele. “When Dad passed nine days later, I realized my call to public service. Our family needed leadership. Our community needed leadership. There was work left undone, and a legacy to carry on inspired by his dream — the dream of this gentle, Hawaiian man from Milolii to build a better Hawaii for us all.”

Kahele was appointed by Gov. David Ige to fill his father’s seat in February 2016, later winning the seat in the 2016 general election.

He’s a combat veteran, a major in the Hawaii Air National Guard and a pilot for Hawaiian Airlines.

To achieve a better future for Hawaii’s children, Kahele said “we need teamwork. We need focus. We need dedicated leadership and an aspirational vision. We need passion and compassion. We need courage and collaboration. We need commitment and humility. We need elected leaders working together, leaders who put the common interests of Hawaii’s people ahead of their own.”

Political opponents of Gabbard have accused her of putting her own political aspirations ahead of the needs of her district, a criticism that could become more of a political liability as her presidential bid draws out.

Gabbard can run for both offices simultaneously, according to the state Office of Elections. She has not responded to repeated questions from the Honolulu Star-Advertiser in recent weeks about whether she does indeed plan to run again for her congressional seat in light of her presidential bid.

On Sunday, CNN’s Jake Tapper asked Gabbard about the challenge from Kahele, which was first reported by the Star-Advertiser on Saturday.

“If you don’t get the Democratic nomination, are you going to try to stay in the House?” asked Tapper.

“We’ll cross that bridge when we get there,” said Gabbard. “I haven’t heard from Sen. Kahele, but whatever he decides to do, I wish him well.”

“Are you concerned at all about a primary challenge?” asked Tapper.

“I’m not thinking about politics right now,” said Gabbard. “I’m looking forward to seeing how I can best serve the country.”

This would be the most formidable challenge Gabbard has had since being elected to Congress in 2012. Gabbard has refused to debate her primary challengers during the last two elections. It would be much more difficult for her to dodge a debate with a state senator.

Asked to comment on Kahele’s challenge, Gabbard’s office said that she “sends her best wishes to Kai Kahele and his family, and thanks them for their service.”