Police said that 52-year-old Kathleen Gregg arrived at her house about 9:30 a.m. EDT to find two men waiting inside. One drew a knife and demanded cash, said Jacqi Smith, a spokeswoman for the Fairfax County Police Department.
One of the men then drove her to a nearby bank while the other followed in another car, Smith said, reporting that after the men received an undisclosed amount of cash from a teller.
As Mrs. Gregg made the withdrawal from a teller, one of the abductors grabbed the money and jumped into the getaway car, reports CBS News Correspondent Teri Okita.
The teller then called the police. Both suspects are still on the run.
Police won't say how much money was stolen.
Sgt. Jeff Gossett of the Fairfax County Police Department said there was "no indication at this time they knew who she was."
Gossett said the senator's wife was "here at the bank, being interviewed by detectives."
"Yes, she's fine," said Mrs. Gregg's mother-in-law, Catherine Gregg, in Nashua, N.H. "It took a lot of courage, a lot of courage for what she went through."
Gossett said the tellers were not aware of any problem as Mrs. Gregg asked to withdraw money from her bank account. Gosset said police have no reason to believe she was targeted because she is the senator's wife. He said he did not know where the senator was at the time.
Gossett said it was similar to a robbery that happened in the county last week, but police have not confirmed whether the two incidents were connected. It's "very bold, it's very brazen," he said.
The bank is in the heart of a busy suburban shopping district about five miles from Gregg's house.
They have three children, two daughters and a son.
"This morning, Kathy Gregg was a victim of a violent robbery. Her life was threatened and it was a terrifying experience," said a statement from Gregg's Senate office.
"Thanks to quick decisions made by Mrs. Gregg, she is doing fine and out of harm's way," it said. "This is an ongoing police investigation, so we have no further comment at this time."
Agents from the FBI's Washington field office are assisting Fairfax County police into the investigation of the abducution of Mrs. Gregg, spokeswoman Debbie Weierman said. She had no other details about the probe.