Mannix, in his letter, cites as evidence for the abortion a 2006 e-mail that appears to be sent by a friend of the woman.
"Rarely have I been confronted with such a difficult decision as to whether to proceed with something of this nature," Mannix writes in his mailing. "But what is on the line here is the character of the person who will represent you in Congress."
After the letter was sent, the woman told the Portland Tribune that Erickson drove her to the abortion clinic, stopping en route to withdraw $300 to pay for the procedure.
Erickson, who has campaigned as a pro-life candidate, strongly denied the charges in a statement.
"These false allegations are exactly the kind of politics that people want changed, and the kind of desperate smear that Kevin Mannix resorts to," Erickson's statement reads. "These unsubstantiated and untrue allegations are from an e-mail from 2006 that no news media reported at the time. They are just as untrue today as they were then."
Download the letter and the e-mail, courtesy of PolitickerOR.