Leipheimer, by the margin of a finger, was the winner of the 75.8-mile stage from Claremont to the top of Mt. Baldy, and Leipheimer's RadioShack teammate Horner just about clinched the overall title with only Sunday's 82-mile ride from Santa Clarita to Thousand Oaks as a wrap-up.
It took three-time race winner Leipheimer 3 hours 33.01 seconds to ride Saturday's stage. Horner was given the same time, with Laurens Ten Dam of the Netherlands and Rabobank third, 43 seconds behind and another American, Tom Danielson of Team Garmin-Cervelo fourth, 1:01 behind.
Horner, 39, has an overall time of 20:50.02, 38 seconds better than Leipheimer and 2:45 ahead of Danielson. Two other Americans — Christian Vande Velde of Team Garmin-Cervelo (3:18 behind) and Tejay Van Garderen of HTC-Highroad (3:23 behind) complete the top five.
"I was hopping the Levi train all the way to the line," Horner said after the stage and as his way of thanking Leipheimer for the support.
Horner also gave big praise to 26-year-old teammate Matthew Busche, a two-time state champion from Wisconsin but otherwise little known to cycling fans. Horner said that when the course began to get steep at the end, "A young man, Mr. Busche, took over and he was very, very impressive. He is a year and a half a pro. His experience is very limited, but his riding ability is very high. He just devastated the field."
For a time Saturday, in the sunny weather and with fans leading the way early on their bikes and on foot so they could line the course, whack noisemakers and clang cowbells, the sense of scandal hovering over the sport, was set aside just for rooting.
Over the last two days, the racing has been overshadowed by pieces of information released from a CBS 60 Minutes investigation about Lance Armstrong.
Hamilton will be on camera saying he saw Armstrong use banned performance-enhancing drugs and 60 Minutes will report that Hincapie made the same claims in testimony to a Los Angeles-based grand jury that is investigating Armstrong and doping in cycling.
After the stage, reporters were asked to keep news conference questions pertinent only to the racing so Leipheimer spoke of Saturday's big climbing stage as akin to the best of the Tour de France.
"The last six kilometers were tough, some of the toughest in the world," Leipheimer said. "It required a lot of fitness, and our team was perfect today and you don't get that much in professional sports, where you experience a day when everything clicks. There was not a lot of talking, everybody was doing everything perfect."
And Sunday's stage will be over and the racers out of town before the 60 Minutes program airs. Questions will remain unanswered.