he man who was at the helm of Oregon's highest-profile terrorism arrest has announced his candidacy for state attorney general, adding to a growing field of Democrats running for the seat.

PORTLAND — The man who was at the helm of Oregon's highest-profile terrorism arrest has announced his candidacy for state attorney general, adding to a growing field of Democrats running for the seat.

Dwight Holton, who served in an interim capacity for 20 months as Oregon U.S. Attorney, was law enforcement's public face during the arrest and arraignment of a Somali-American teen charged with attempting to detonate a weapon of mass destruction at a 2010 Christmas tree-lighting ceremony.

Holton over the past few years has had no fear of putting himself in the public eye, as he did during the 2010 arrest of Mohamed Mohamud, who is expected to face trial this year.

Holton, 46, was assigned to the top job at the U.S. attorney's office in February 2010 and held it until last October, when Amanda Marshall was officially sworn in. She was President Barack Obama's selection for the job.

In an email seeking support from Oregon attorney associations, Holton pitched himself as an effective leader who got results in his short stint at the helm of the U.S. Attorney's Office.

"Throughout my career I have held one central principle: be on the side of the people," Holton wrote in the email sent Wednesday morning. "I am asking for your support because I believe that now more than ever, we need an Attorney General with those values and a track record of leadership, experience and results."

The letter also includes references to support of environmental causes and education — two powerful lobbies in Salem. A website launched Wednesday highlights his focus on reducing prescription drug abuse, focusing on civil rights and fighting white-collar crime.

The son of former Virginia governor Abner Linwood Holton, Holton graduated from the University of Virginia's law school in 1996. As a young assistant U.S. attorney in New York, Holton prosecuted murder, terrorism and organized crime cases. He joined the U.S. attorney's office in Oregon in 2004.

Current Oregon Attorney General John Kroger has said he will not run for reelection, citing an unspecified health condition.

No Republican has announced plans to run. The party has had difficulty getting attorney general candidates and four years ago actually nominated Kroger.

Holton's top competition is expected to be fellow Democrat Ellen Rosenblum, a retired Oregon Court of Appeals judge with experience as a federal prosecutor. Since announcing her intention to run for office on Jan. 4, Rosenblum has collected more than $15,000 in contributions.

Rosenblum said Wednesday that her experience in the state court system, both as an attorney and a judge, gives her experience Holton doesn't have.

"Mr. Holton has never been a lawyer in the state courts of Oregon," Rosenblum said. "That's a whole lot different system. He just became a member of the bar two years ago."

Holton joined the Oregon bar on March 20, 2009.

"The difference is the depths of my knowledge," Rosenblum said.

Rosenblum carries with her the endorsements of former Gov. Barbara Roberts and former Attorney General Dave Frohnmayer.

Portland attorney Katherine Heekin has also organized a campaign committee with the Oregon Secretary of State's Office.

Holton was also key in getting the city of Portland to rejoin the federal Joint Terrorism Task Force. The city had pulled out of the task force — the only city to do so —over concerns that its police force could be involved in investigations that violated state laws against targeting people based on race or religious belief.

Walking a narrow line, Holton brought top FBI officials to Oregon to convince the city council that the effort was worthwhile. The city drew up a new agreement with federal officials that provides "an unprecedented commitment to civil rights," as Holton put it in a letter to the city's mayor.

A longtime Democrat, Holton met his wife at the party's 1992 national convention.

He counts Kroger, the current Attorney General, as a friend. Kroger has more than $280,000 in his campaign fund that he can distribute to other campaigns.