A woman campaigning for John McCain in Pittsburgh claims she was mugged by a knife-wielding man who then “carved the letter ‘B’ into her face” after spotting a McCain bumper sticker on her car, police said yesterday.

Ashley Todd, 20, a Texas native, told police she was using a Citizens Bank ATM at about 8:55 p.m. Wednesday when a man rushed up, put a 4-to-5-inch knife to her throat and demanded money.

UPDATE: Attack ‘Victim’ Changes Her Story

She said she gave him $60, and “she remembers moving away from [him],” said police spokeswoman Diane Richard.

“Then, she said, he noticed a McCain bumper sticker on her car and became very angry.

“[She] reported he punched her in the back of the head, knocking her to the ground, and continued to punch and kick while threatening to teach her a lesson for being a McCain supporter.”

Richard said the victim said the attacker called her “a lot of names and stated that ‘You are going to be a Barack supporter’,” pinning her hands down while carving the letter B on her face “using what she believed to be a very dull knife.”

Pennsylvania has been a key battleground state, where McCain and Barack Obama have both been campaigning hard.

The attack lasted 5-10 minutes, after which the suspect fled. Todd said she drove to a friend’s house, cops said. That friend called police.

When an officer offered her medical attention, Todd said she’d go to the hospital the next day, Richard said.

Cops are treating the alleged attack with skepticism, unnamed law-enforcement sources told TMZ.com. A source told The Post that cops were considering administering a lie-detector test.

Richard would only say the investigation was continuing. Todd, who was being re-interviewed last night, remained inside the stationhouse early today.

“We can’t substantiate that it was politically motivated,” Richard said early today. She said police are trying to retrieve surveillance tape from the area.

After the attack, Todd posted this message on a GOP college blog: “Thanks to everyone for their thoughts and prayers – I’m phonebanking, so let’s all work together and get John McCain elected.”

It also appears she was using Twitter – a social-messaging Internet application for wireless devices – around the time of the reported attack.

In one post, she wrote, “Stubbornly searching for a Bank of America to avoid ATM fees,” she said.

Shortly after, she wrote, “Pretty sure I’m on the wrong side of Pittsburgh.”

McCain’s campaign said he and Sarah Palin spoke to Todd’s family yesterday.

Obama’s campaign released a statement, saying, “Our thoughts and prayers are with the young woman for her to make a speedy recovery, and we hope that the person who perpetrated this crime is swiftly apprehended and brought to justice.”

Ethan Eilon, executive director of the College Republican National Committee, the group Todd was volunteering with, said he’d spoken to her several times over the day.

“She’s recovering. Obviously, she’s had a pretty rough 24 hours,” he said.

With Post Wire Services

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