High-Speed Rail Authority chairman Tom Umberg

But the authority needs $2 billion a year until 2033 to extend from there northward toward Sacramento and San Francisco and southward to Los Angeles and San Diego.

Where that money will come from is the biggest question facing the authority?

In his quest to offer more funding, President Barack Obama faces stiff opposition from members of Congress who have stumped on cutting back federal spending.

The state has about $6 billion in bonds it can make available and asking voters for more might be tough in the immediate future. The state doesn't want to release the money it has until more of the state's debt burden is squashed.

The authority says it can get almost $20 billion from private companies, but their assertions seem flaky to many experts.

The authority's revised business plan, released Tuesday, says the $98 billion rail line will make money and be smarter investment than expanding highways and airports.

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