Updated

by Kara Rowland

A Tennessee Republican once thought to be a shoo-in for re-election could now be facing a competitive race after tales of a thorny romantic entanglement have come back to haunt him.

Rep. Scott DesJarlais, R-Tenn., a practicing physician, recently admitted to carrying on a consensual relationship with a patient back in 2000 -- something forbidden by the state medical board. Revelations of the dalliance surfaced last week, when the Huffington Post reported that the pro-life Republican pressured the woman to abort a potential pregnancy, according to what it cited as a transcript of a recorded phone call between the two.

DesJarlais said there ended up being no pregnancy or abortion, but news of the imbroglio has nevertheless rocked an otherwise sleepy race.

A watchdog group has filed a complaint with the state medical board, a move that could put the lawmaker's medical license in jeopardy. Noting he was legally separated from his then-wife, DesJarlais apologized in a letter to supporters and dismissed the controversy as irrelevant to his congressional service.

"I have a strong pro-life record in Congress and history of fighting for values important to Tennesseans," he wrote. "I hope you will judge me on these facts because that is who I am."

The scandal has created an opening for challenger Eric Stewart, a state senator who is now trailing DesJarlais by 4.9 points, according to Myers Research, a Democratic polling firm that describes the race as a statistical dead heat. By contrast, Republican presidential hopeful Mitt Romney leads President Obama by 18 points in the state.

"The people of Tennessee deserve to have a congressman to represent them that has not caused the type of national embarrassment that we've seen from Congressman DesJarlais," Stewart said in a statement. "He's violated his oath of marriage, the oath he took as a doctor, and the trust of the voters."