Defending champion Catherine Ndereba (search) of Kenya became the first woman to win a fourth Boston Marathon on Monday, and Ethiopia's Hailu Negussie (search) won the men's race to break the Kenyan stranglehold on the world's oldest annual marathon.

Alan Culpepper was fourth — almost two minutes behind Negussie — the best finish for an American since Dave Gordon was fourth in 1987.

"Catherine the Great" pulled away from Ethiopia's Elfenesh Alemu in the last three miles to win by 1:52 in an unofficial time of 2 hours, 25 minutes, 12 seconds.

Negussie, who was fifth last year, finished in an unofficial 2:11:45 to earn the $100,000 prize. Kenyans had won 13 of the previous 14 men's races, but this year they'll have to settle for a record-setting victory by Ndereba.

Alemu had a share of the lead from the fifth mile in Framingham, pulling away from the pack at Wellesley College before the midway mark. Ndereba was as many as 80 seconds behind before closing the gap and pulling even with Alemu at the crest of Heartbreak Hill, about two hours into the race.

They ran side-by-side past Boston College onto Beacon Street before Alemu fell back at Cleveland Circle in Brookline.

"I guess she fell from my pace," Ndereba said. "I didn't know if I was going faster or not. As I kept accelerating, I passed all those who were leading."

Ernst Van Dyk of South Africa won his fifth consecutive wheelchair race, finishing in 1:24:11 — almost six minutes ahead of countryman Krige Schabort. Van Dyk, who set a world best of 1:18:27 last year, is the first man to win five Boston wheelchair races in a row; Franz Nietlispach has also won five, but only four were consecutive.

Cheri Blauwet, of Palo Alto, Calif., also repeated in the wheelchair division, winning by 3:08 in 1:47:45.

The 109th edition of the race was replete with tributes to two-time winner Johnny Kelley, who died in October at the age of 97. Kelley finished second a record seven times and lined up at the start on Patriots Day 61 times.

Kelley's bib No. 61 was retired this weekend. A picture of him has been hung in the Cheers bar not far from the finish line.

Runners were serenaded with "Young at Heart" before the race, even though Kelley wasn't there to sing it. And 1985 winner Jacqueline Gareau, better known as the woman who "finished" second to Rosie Ruiz, served as grand marshal — a position created to honor Kelley when he became too frail to continue running.

Gareau got out of the car in the Back Bay and ran to the finish line to break the tape, something she didn't do in her victory after Ruiz entered the course near the finish line and pretended to be the winner. She was given an olive wreath and the Canadian national anthem was played.

A field of 20,453 runners started the world's oldest annual marathon in Hopkinton. With temperatures near 70 degrees at the start, state police set up four aid stations along the route to help runners who have problems because of the heat.