Switzerland's Fabian Cancellara won the Amgen Tour of California prologue today, unofficially covering the 2.4-mile course through the streets of downtown and midtown Sacramento in 4 minutes, 32.90 seconds.

The Team Saxo Bank rider will wear the yellow jersey for Sunday's first stage, 107.6-mile test from Davis to Santa Rosa.

Defending Tour of California champion Levi Leipheimer finished second with a 4:34.11 effort, followed by American David Zabriskie in 4:35.51.

Seven-time Tour de Fance champion Lance Armstrong finished in 4:37.17.

"I'm for sure happy," said Cancellara, who won the Tour of California prologue last year. "It's the first race (of the year). You never know how good you really area."

Leipheimer sounded assured about his chances to win the Tour for the third time after finishing the prologue so close to the lead.

"After today, I feel very confident," said Leipheimer from Santa Rosa. "To be so close to Fabian, I think, is a good sign."

Today's stage could include bad weather, and periods of rain are forecast.

"We've all been professionals for a long time," Leipheimer said. "We certainly had very bad (weather) days on the bike. We know what it's like.

"In your head you have to be ready for the worst."

Riders streaked over the Capitol Mall course as large crowds cheer and more than a few clang cowbells, happy to have the event underway without rainfall.

The first rider of the first day of the nine-day race headed down the start ramp at 1:30 p.m. The weather was iffy all morning, some blue skies, then plenty of clouds.

But right at the start of the race the skies were as blue as they were all day, which means safe cycling, the riders not having to deal with wet pavement at the corners.

Many cycling fans smiled when asked about the weather as they lined the streets of Sacramento in jackets.

Most came prepared for showers and said they didn't mind braving the chill as long as the dark clouds held a little longer.

"We got lucky," said Eve Taylor after setting down her camera along N and 11th streets.

With rain clouds moving in over and the temperature dropping, Dave Talpas said he planned to stick it out until he got a glimpse of Lance Armstrong.

"The weather put a damper on things, but it hasn't detoured people."

As Armstrong raced down L street, Stephen Fullenwider of Citrus Heights held up his camera phone with glee.

"This is what we've been waiting for," he said. And shortly after as a light sprinkle began, the race came to a close.

"This has been awesome," Fullenwider said. "It's great to see an event like this in Sacramento."

The crowds appeared to be larger than previous times the tour has come to Sacramento. Organizers expected at least 75,000 to attend, but no official estimate is yet available.

In addition to crowd that is four rows deep at some locations, other fans gathered around team buses. Inside the buses with their darkened windows are cycling team members waiting to take to the course.

Team buses are parked all over downtown but two of those parked the closest to the start line were those of Floyd Landis and Lance Armstrong. All day, a crowd of a couple hundred fans stood around the Team Astana bus, which apparently may contain the seven-time Tour de France champion.

Generally, team members sits inside the buses until it is time for an individual rider to exit and get on a trainer bike to warm up in a cordoned off area. Landis has popped his head out of his bus a couple of times -- prompting a big cheer.