In 2006, incumbent Democratic State Representative Brad Avakian decided to retire to run for the Oregon Senate. She ran for the open seat in Oregon's 34th House District and defeated Republican Joan Draper 62%-36%. On April 30, 2008, Bonamici was appointed by Commissioners from both Washington and Multnomah counties to represent Oregon's 17th Senate District. The seat became vacant when Avakian was appointed Commissioner of the Oregon Bureau of Labor and Industries. She was sworn in on May 19, 2008. Bonamici was unopposed in the November 2008 special election for the balance of Avakian's four-year term, and was elected with 97 percent of the vote. In 2010, she won re-election with 64% of the vote.
;Special election In early 2011, Bonamici's name was floated as a possible successor to then-Congressman David Wu after The Oregonian and Willamette Week reported Wu exhibited odd behavior and clashed with his staff in the midst of apparent mental illness during the 2010 election cycle. Following Wu's resignation from Congress, Bonamici announced her candidacy for the special election to replace him, touting endorsements from former Governor Barbara Roberts, former Congresswoman Elizabeth Furse, and incumbent Oregon Attorney GeneralJohn Kroger, among others. On November 8, 2011, Bonamici won the Democratic Party of Oregon's nomination, winning an outright majority of the vote in every county in the district and capturing 66% of the vote overall, with a 44-point margin over second-place finisher Brad Avakian. She faced Republican nominee Rob Cornilles in the special election on January 31, 2012, winning by a 14-point margin. Prior to her election to Congress, Bonamici resigned from the Oregon Senate on November 21, and was replaced by Elizabeth Steiner Hayward in December. ;2012 regular election In November 2012, Bonamici won re-election to her first full term with over 60% of the vote.
Legislation
On July 31, 2014, Bonamici introduced the Tsunami Warning, Education, and Research Act of 2014 into the House. The bill would authorize the National Oceanic and Atmospheric Administration to spend $27 million a year for three years on their on-going tsunami warning and research programs. Bonamici said "the coastlines of the United States already play an integral role in the economic prosperity of this country and we must strengthen their preparedness and resiliency so they can continue to play that role going forward." She added that this bill "will improve the country's understanding of the threat posed by tsunami events" because it will "improve forecasting and notification systems, support local community outreach and preparedness and response plans, and develop supportive technologies."
Committee assignments
Committee on Science, Space and Technology
*United States House Science Subcommittee on Environment
* In the 2012 election, Steve Reynolds was co-nominated by the Libertarian and Pacific Green parties.
Personal life
She is married to Michael H. Simon, a federal judge. They have two children, Andrew and Sara. Bonamici was raised Episcopalian and Unitarian, and now attends synagogue with her husband, who is Jewish, and their children.