Mary Kate Bailey of Arlington used a conservative but perfectly executed race plan to become the first active duty Marine to win the Marine Corps Marathon women's race since Joanna Martin in 1979.

Bailey, a Naval Academy Class of '98 graduate and captain stationed at Quantico, took the lead from fellow Marine and early leader Jennifer Ledford, 24, near the 15-mile mark and rolled to the finish unchallenged in 2 hours 48 minutes 31 seconds -- a personal best by 14 minutes.

Kim Fagen, 34, a Navy flight surgeon from San Diego, held the lead at times in the first few miles and finished second in 2:51:17. Ledford, however, succumbed to the warm conditions and her fast start. She struggled to finish 11th in 3:09:01, running the last 10 miles at an average of almost nine minutes per mile after going through the first 10 miles in 62:20, an average of 6:14 per mile.

"My entire focus was to run a smart race," said Bailey, 29. "The first few miles I felt were too slow, but thank God my coach held me back."

Bailey ran the first 14 miles with her coach, George Buckheit, who insisted upon a conservative pace.

"But after 14 miles, I was toast," said Buckheit, who dropped out at that point. "Then she was on her own."

Bailey has three brothers, all Marines, who supported her along the course; her father is buried in Arlington National Cemetery near the 25-mile mark.

"It's an honor to run for the Marines," Bailey said. "Honestly, I think about the Marines stationed in the Middle East, and running 26 miles is just a cakewalk."

Bailey ran 3:26 last year at the Marine Corps Marathon, six weeks after giving birth to a daughter. She finished third in 2002 in 3:02, and started yesterday with the intention of running 2:45 and winning.

Despite what appeared to be an attempt to wrap up the race early, Ledford said that she, too, expected Bailey to be a factor.

"I was looking for her," said Ledford, a first lieutenant and student aviator stationed in Pensacola, Fla. "I'm really proud of her."

Bailey returned the compliment, "This was [Ledford's] first marathon, and she'll learn to do better."

Third-place finisher Suzanne Clemmer, 24, from Gastonia, N.C., entered via the lottery system and made the most of her first Marine Corps Marathon. Clemmer said she was inspired to run by her brother, a Marine stationed in Okinawa.

Like race-winner Bailey, Clemmer started conservatively and moved up throughout the race.

"I didn't realize I was third until near the end when a motorcycle started riding alongside me," Clemmer said. "But this race isn't about winning -- it's all about the challenge."

Mary Kate Bailey celebrates becoming the first active Marine to win the women's race in 25 years.