Vito J. Fossella, who represents Staten Island and parts of Brooklyn, was arrested some time between midnight and 2 a.m., said Lt. Ray Hazel, spokesman for the Alexandria Police Department.
He was charged with driving while intoxicated as a first offense, Hazel said, which under Virginia law requires a blood-alcohol level of 0.08 percent or higher.
In a statement Thursday, Fossella apologized for his conduct.
"Last night I made an error in judgment," Fossella said. "As a parent, I know that taking even one drink of alcohol before getting behind the wheel of a car is wrong. I apologize to my family and the constituents of the 13th Congressional District for embarrassing them, as well as myself."
Hazel said he could provide no further details on the arrest, including Fossella's exact blood-alcohol level or where in the city he was arrested.
Fossella, 43, is the lone Republican member of the New York City congressional delegation.
He faced a surprisingly strong re-election challenge in 2006 and is bracing for a similar fight this year. His candidacy has drawn the support from national Republican leadership in recent weeks, including Vice President Dick Cheney.