PORTLAND, Ore. -- Oregon Right to Life says 5th District congressional candidate Mike Erickson "has become so tainted" by claims that he impregnated a girlfriend and paid for her abortion that he should quit the race for the Republican nomination.

Erickson calls the claim by opponent Kevin Mannix totally false and a "desperate smear."

Erickson, who is funding much of his own campaign, has raised vastly more money than Mannix.

Mannix mailed the accusation to Republican voters Monday but the letters contained no complete names or evidence.

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Erickson responds to allegations

Mannix letter about Erickson

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Erickson seeks the right-to-life vote in the race to run in November to replace Democratic Rep. Darlene Hooley, who is not seeking re-election.

Mannix's letters to voters contain a 2006 e-mail written by someone named "Kristi," who identified herself as a friend of the woman.

"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.

The letter to Mannix campaign director Amy Langdon from Oregon Right to Life Director Gayle Atteberry carries the logo of the Mannix campaign.

A cover letter said Right to Life officials had talked to "Tawnya," the woman Erickson is supposed to have impregnated.

"She is very credible and remains, to this day, devastated over the events," Thursday's letter said.

"Honestly, Mike should withdraw from the race," said the letter to Langdon.

Mannix said told The Associated Press Thursday that he has heard nothing from the Erickson campaign about the allegation.

Calls to Erickson's campaign manager, Cary Evans, were not immediately returned.

"All he has done is attack the messenger himself. He needs to respond to their story and has not," Mannix said of Erickson. "I don't think he exists. He has disappeared from sight other than his cash machine."

Atteberry said Thursday that Erickson told the organization he took Tawnya to a "doctor's office" and gave her money but did not know she planned an abortion.

An Erickson television ad airing this week accuses Mannix of making false and unsubstantiated accusations but does not mention the abortion issue. It claims Mannix voted for 83 tax increases during his legislative career.

Mannix said one of the two women, Kristi, told him she was a Democrat and normally would not support his candidacy. "It has to do with hypocrisy," he said.