SALEM, Ore. -- The hard-fought battle for an open congressional seat took a nasty turn Monday when candidate Kevin Mannix accused his opponent, Mike Erickson, of impregnating a young woman in 2000, then dropping her off at a clinic to have an abortion.

AP

Former Oregon GOP chairman Kevin Mannix.

Erickson's campaign spokesman emphatically denied the allegation, calling it a "desperate smear" by Mannix, who has lagged far behind Erickson in fundraising and has been unable to match Erickson's blizzard of TV ads.

  Erickson: Mannix using 'smear' tactics

Mannix, a former lawmaker and gubernatorial contender, airs the accusation against Erickson in a letter sent to the homes of 5th District Republicans who haven't cast their ballots yet in advance of next Tuesday's GOP primary.

 Read the letter (PDF)

The letter contains no complete names or evidence and instead cites a 2006 e-mail purportedly written by someone identified as "Kristi," who says she is the friend of the woman, "a single mom," who allegedly was impregnated by Erickson and got the abortion.

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In the e-mail, Kristi asserts that Erickson was being hypocritical for running as a "pro-life, pro-family" candidate.

"Where were these ideals in the year 2000 when he drove my friend (whom he impregnated) to an abortion clinic in NE Portland, handed her some cash, and left her at the door?" the e-mail said.

Kristi's e-mail, which Mannix included with his letter, also accused Erickson of "having wild parties involving cocaine use on his house boat" in the same year.

Erickson's campaign spokesman, Cary Evans, said the allegations "are absolutely untrue" and that Mannix has aired them with only a week to go before the election "because he knows he is losing" the race.

"These unsubstantiated and untrue allegations are from an e-mail from 2006 that no news media reported at the time," Evans said. "They are just as untrue today as they were then."

Erickson, a wealthy Lake Oswego businessman, and Mannix, have been locked in a tough fight for the GOP nomination in hopes of replacing Democratic Rep. Darlene Hooley, who announced in February that she wouldn't run for re-election.

The latest federal campaign finance reports show that Erickson has raised $921,000 -- including $590,000 in loans from himself -- compared to Mannix's total fundraising of $187,000.

Erickson has used his financial advantage to blanket the airwaves with TV ads, including one that blasts Mannix for supporting tax hikes as a legislator.

In his letter, Mannix said he felt it was important for 5th District Republicans to be informed of the "extremely disturbing information about my opponent, and the disrespectful way he treated a young woman."

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"Many people have suggested to me that I allow some 'other party' to share this information with you so that I can stand by and watch the situation develop," Mannix wrote. "I believe it is important for me to take personal responsibility for sharing this story."