California voters are green-lighting the nation's most ambitious high-speed rail system, approving a nearly $10 billion bond to speed bullet trains capable of topping 200 mph between the state's major metropolitan areas.

Proposition 1a passed with 52 percent support even as voters rejected most other high-cost initiatives on Tuesday's ballot. It will fund the first phase of what is projected to be a $45 billion project built with state, federal, local and private money.

Backers sold the long-delayed proposal as an innovative alternative to soaring airfares and gas prices. In the closing weeks of the campaign, they touted estimates that it would create nearly 160,000 construction-related jobs and 450,000 permanent jobs.

"They (voters) may be looking at this as a public works program," Field Poll director Mark DiCamillo said Wednesday. "That might have pushed this over the top."

The measure survived even as voters rejected two costly proposals promoting clean energy and two aimed at altering crime fighting. However, they approved measures borrowing money for veterans and children's hospitals.

"In our state, transportation is always a big issue," said Mark Baldassare, president of the nonpartisan, nonprofit Public Policy Institute of California. "A lot of people have a sense that maybe that (bullet train) is something I can use at some point. It's something they can relate to."

The 800-mile rail line would link Anaheim, Los Angeles, Fresno and San Francisco. Planners eventually want to include Sacramento, San Diego and Oakland.

"Californians decided to reduce our oil dependence, to build alternatives to traffic and long airport lines, and to help solve global warming. Californians were also voting to boost the economy," Emily Rusch of the advocacy group CALPIRG.

The $9.9 billion proposition includes $9 billion for bullet trains and $950 million for conventional commuter and intercity rail, including trains to connect travelers with the high-speed train system.

"The citizens of California have put the 21st century golden spike in the ground," Quentin Kopp, chairman of the California High-Speed Rail Authority, said in a statement referring to a long-gone era when trains were the primary mode of long-distance transportation.

The plan still could be derailed, however.

Proponents are counting on the federal and local governments and private investments to help with the estimated $45 billion total cost.

One environmental group, the Planning and Conservation League, already has sued over plans to route trains through the coastal mountains from the Central Valley to the San Francisco Bay area through the Pacheco Pass southeast of San Jose. The league wants the rail line to follow more urban route through the northern Altamont Pass east of San Francisco.

Opponents also fear the measure might not pay for itself and require ongoing subsidies.

But with enough money, supporters say the first trains could be running in six years and the entire system could be completed by 2020.

Florida and Midwestern states are among regions waiting to follow California's lead, CalPIRG's Rusch said in a statement.

California's effort has been 14 years in development, since it was first recommended by a commission in 1994. Two years later, lawmakers created the nine-member authority to oversee planning for the bullet trains. Legislators approved a bond measure for the November 2004 ballot, then delayed it until 2006 and again until this year in deference to other construction borrowing measures.

The long delay may have played in the measure's favor, said Baldassare of the public policy institute.

"It's an idea, a concept, that Californians were familiar with," Baldessare said.

The measure passed without support from Gov. Arnold Schwarzenegger. The governor supported the concept in an opinion piece, but concentrated in this election on promoting a legislative redistricting measure and opposing a drug rehabilitation initiative.