By Teresa Carson

Suzanne Bonamici, a former Federal Trade Commission lawyer who most recently served as a state senator, garnered 88,925 votes to defeat Republican businessman Rob Cornilles, with 64,003 votes, to win the contest in Oregon's First Congressional District.

"With this victory, the Democratic Party of Oregon once again delivered a commanding voter turnout operation, strengthening our national reputation for state-level field organizing," the state party said in a statement Tuesday night.

Cornilles conceded his defeat in a speech to supporters at the World Forestry Center in Portland.

The district includes part of Portland, Nike Inc.'s headquarters, much of Oregon's high-tech industry, affluent suburbs and areas dependent on farming and fishing.

As in all Oregon elections, the race was conducted by mail. Ballots were distributed to voters earlier this month and had to be returned by 8 p.m. Tuesday night.

The contest between Bonamici and Cornilles has attracted an unusual level of interest for a traditionally safe Democratic seat, drawing almost $2 million in independent expenditures since November.

The western Oregon district has sent only Democrats to the U.S. House of Representatives since 1974, and Democrats hold a 12-percentage-point advantage in voter registration over Republicans.

President Barack Obama easily carried the district in 2008 and Wu fended off a challenge from Cornilles in a 2010 election year that heavily favored Republicans elsewhere in the country. Polls showed Bonamici with a considerable lead.

(Additional reporting and writing by Steve Gorman; Editing by Cynthia Johnston and Peter Bohan)