The Democrat led GOP businessman Rob Cornilles 52 percent to 41 percent in a poll paid for by the liberal website Daily Kos and the Service Employees International Union.
The survey comes just a few days after Democrats reserved $1 million in TV ad time on behalf of Bonamici ahead of the Jan. 31 special election. The high-dollar reservation raised eyebrows, even though party strategists said the spending was nothing more than an insurance policy for holding the seat.
The Democratic firm Public Policy Polling conducted the survey, which took the opinion of 979 likely voters in the district Dec. 13-14. The poll had a margin of error of 3.1 points.
Bonamici and Cornilles are running to succeed former Rep. David Wu (D), who resigned earlier this year.
The 1st district should be solid Democratic territory. President Barack Obama carried it with 61 percent of the vote in 2008.
Hillary Rodham Clinton, center, along with former Secretary of State Madeleine Albright, right, and Annette Tilleman-Dick, left, wife for former Rep. Tom Lanots, D-Calif. Clinton was honored with the Tom Lantos Human Rights Prize during a ceremony last week at the Cannon House Office Building. Previous winners include the Dalai Lama and Elie Wiesel.
Each year since 1990, CQ Roll Call has reviewed the financial disclosures of all 541 senators, representatives and delegates to determine the 50 richest members of Congress. This year's report, derived from forms covering the calendar year 2012, shows it took a net worth of $6.67 million to crack the exclusive club.