The last time Clinton was in Orange County was 14 years ago when he helped Sanchez win her seat representing the 47th Congressional District.
"Here's what I think about this race: I think you have two American success stories, two immensely impressively individuals, with radically different ideas about how to give the rest of America the same success stories," said Clinton.
Sanchez faces the toughest challenge of her 14 years as she tries to hang on to her seat in the 47th Congressional District, an area of central Orange County where nearly half of voters are registered Democrats. The district is more than 70 percent Latino.
"I have fought for you for healthcare. I have fought to lower prescription drug costs. We made sure the middle class got tax cuts," said Sanchez.
Sanchez is the daughter of immigrants. Her main opponent is Republican state Assemblyman Van Tran. He fled Vietnam with his family before the fall of Saigon. He's not worried by the former president's visit to support Sanchez.
"The race is a toss-up and the incumbent is very worried and she should be, because in 14 years that she's been a member of Congress, she's only passed one bill, and that was to name a post office," said Tran.
Tran has served in the state assembly for five years. He and his wife and two children hit the streets of Orange County, knocking on doors Friday.
Tran and Sanchez faced off in their first debate this week. Sanchez supports the federal stimulus package. Tran criticized government overspending and questioned where all the jobs are.
Sanchez made national headlines last month when she said the Vietnamese were trying to take her seat during a Spanish-language TV interview. She later said it was misinterpreted. Tran criticizes her for not apologizing for the remark.
Police estimated the crowd at the Friday's rally for Sanchez at about 1,000 people. A couple dozen were Tran supporters.