6:15 PM: The man who broke the course record during last year’s San Francisco Marathon returned today to win the half marathon, and plans to try out for the Olympics in January.

“I had a great experience last year, I’m glad to be back,” said Keith Bechtol, a graduate student at Stanford University. Bechtol won his first-ever marathon in San Francisco last year, but ran four others in California, Chicago and Minnesota.

“This is the start of my training cycle, so it’s a good checkpoint,” Bechtol said. “I wasn’t expecting to run so well today.”

According to unofficial results, Bechtol finished the 13.1-mile race with a time of one hour, five minutes and 19 seconds, only 17 seconds longer than the course record.

More than 25,000 runners ran the challenging course, which started near the Ferry Building on the Embarcadero, followed the Bay into the Presidio, over the Golden Gate Bridge and back, and through the western side of the city back to the Ferry Building.

The winner of the full marathon, Michael Wardian, a 37-year-old endurance athlete from Virginia, finished third in the 135-mile Badwater Ultramarathon only three weeks ago.

According to unofficial results, he finished today’s marathon in two hours, 27 minutes and six seconds, despite struggling with stomach flu last night.

“It was nice to be able to hold in there and pull through the win, but it wasn’t as fast as I ran last year,” Wardian said.

Wardian has a full slate of races coming up, including representing the U.S. at the International Association of Ultra Runners 100K World Championship race in the Netherlands, the North Face Endurance Challenge in Kansas City, and the New York City Marathon. He said he races about 50 times a year.

Wardian is a semi-professional athlete with sponsorships from North Face, Power Bar and Marathonguide.com. He also holds a full-time job as an international shipbroker and has two young children, ages two and five.

This year’s winner plans to run in January’s Olympic trials in Houston with Bechtol, who narrowly beat Wardian in last year’s San Francisco Marathon.

“I was very impressed by how he ran,” Wardian said.

Not everyone who participated in today’s race intends to be an Olympic competitor.

Many were running to meet personal goals, get some exercise and enjoy the sights of San Francisco.

Matt Brennan ran today’s half marathon to celebrate his 23rd birthday. Brennan recently graduated from Georgetown University and is in San Francisco as a volunteer with the Jesuit Volunteer Corps. He ran his first marathon in Oakland in March.

“I didn’t want to kill myself so I went down to the half,” he said.

His friend and volunteer colleague Marin Riley ran her first marathon today.

“I was really happy I broke the four-hour mark,” she said. She said the highlight was running over the Golden Gate Bridge.

“That was an absolutely spectacular experience,” she said.

Stu Matthews, a 27-year-old Systems Administrator from San Francisco also ran his first marathon today in four hours and seven minutes. He said he enjoyed the experience and will likely run another marathon next year.

But after enduring today’s 26-mile race, Matthews said he is “extremely sore and needing a sandwich.”

The race attracted runners from throughout California, the United States, and countries like Switzerland, Mexico and the Virgin Islands.

Approaching the finish line, participants passed under the Bay Bridge and were greeted by spectators lining the road, cheering the arriving runners for hours.

Some runners were smiling and jubilant, others red-faced and panting as they crossed the finish line, where volunteers offered them blankets, water, fruit and pastries before they rejoined the crowd to greet friends and family.

A stage with a bicycle-powered sound system was provided by the Berkeley-based organization Rock the Bike, with Latin-style music performed by Oakland group LoCura.

The second Munchkin Kids Run was also held today for 2-11 year-old children. Eight-time Olympic gold medal winning speed skater Apolo Ohno joined the kids on their mile-long run, after he had already run the 5K route twice, organizers said.

As of 2:00 p.m. no serious injuries had been reported among the runners or the estimated 100,000 spectators, said marathon spokeswoman Kelli Wynne.

1:21 PM: The man who broke the course record during last year’s San Francisco Marathon returned today to win the half marathon, and he said he plans to try out for the 2012 Olympics in January.

“I had a great experience last year, I’m glad to be back,” Stanford University graduate student Keith Bechtol said. Bechtol won his first-ever marathon in San Francisco last year, and ran four others in California, Chicago and Minnesota.

“This is the start of my training cycle, so it’s a good checkpoint,” Bechtol said. “I wasn’t expecting to run so well today.”

According to unofficial results, Bechtol finished the 13.1-mile race with a time of one hour, five minutes and 19 seconds, only 17 seconds shy of the course record.

More than 25,000 competitors ran the challenging course, which started near the Ferry Building on the Embarcadero, followed the coastline into the Presidio, over the Golden Gate Bridge and back, through the western side of the city and finishing back at the Ferry Building.

The winner of the full marathon, Michael Wardian, a 37-year-old endurance athlete from Virginia, ran the 135-mile Badwater Ultramarathon only three weeks ago. According to unofficial results in today’s marathon, he finished in two hours, 27 minutes and six seconds, despite struggling with a stomach flu last night, event organizers said.

As of 12:00 p.m. no serious injuries had been reported among the runners or the estimated 100,000 spectators gathered along the route, marathon spokeswoman Kelli Wynne said.

Scott Morris, Bay City News

Want more news, sent to your inbox every day? Then how about subscribing to our email newsletter? Here’s why we think you should. Come on, give it a try.