Today is a consequential day in the future of high speed rail in America. The California State Senate will vote to approve initial funding for the state’s HSR project through a bond issue. The Assembly has already passed the funding, but observers expect a tougher road in the Senate. Governor Jerry Brown has been a strong supporter of the project, but he’ll have to convince 21 of the 25 Democrats in the Senate in order to get passage. State Republicans are all opposed in lockstep, and six Democrats have expressed reservations.

Senator Leland Yee, a Democrat from San Francisco, said the plan’s supporters have their work cut out winning him over, a sentiment other Democratic senators have shared with Reuters in recent days.

“Right now, my choice is not to support this particular arrangement,” Yee said [...]

It remained uncertain whether enough Democrats in the Senate would rally behind that plan, which does not account for the tens of billions of dollars needed to fully extend the rail system across the state.

“That is the elephant in the room,” said Democratic Senator Mark DeSaulnier, who is working on an alternate plan to present to his caucus.

If San Francisco’s Senator is opposed, you know you have an uphill battle.

This is crucial, because the federal Department of Transportation has made clear that they will revoke their $4.3 billion in federal funds for California’s HSR project, most of which came out of the stimulus package, if the state doesn’t approve funding today. This would undoubtedly stall the project, perhaps permanently. And California is probably the furthest along of any state on a high speed rail system. The demise of that tentpole project would be a huge blow.

The high speed rail project has been mired in controversy after a series of increased funding estimates and questions about ridership. The same people fighting against HSR have been the ones elevating the costs, in many cases, because of changes to the route necessitated by NIMBYism. State Republicans and budget scolds have engaged in an effective messaging campaign against the project, led by one-sided reports from the state legislative analyst, California’s version of the Congressional Budget Office. Other independent reviews have come to different results, showing it would cover its operational costs through ridership.

A recent set of changes to the plan involving the use of existing commuter track and other tweaks have reduced the cost back to about $68 billion. But the state has only confirmed funding for about $14 billion of that: around $10 billion in a voter-approved bond sale, the authorization of which is what the state Senate will vote on today, and that $4.3 billion in federal funds. If approved, the first batch of funding – $3.2 billion from that federal kitty, as well as $2.6 billion in bond funds – would go toward construction of the rail line in the Central Valley, as well as nearly $2 billion for improvements to existing track in San Francisco and Los Angeles to handle high speed rail cars.

Another factor in the vote could be an ill-timed Field Poll on the November ballot measures. Governor Brown placed a tax levy on the ballot that would bring in between $5-7 billion and stave off crippling budget cuts, particularly to public education. But the Field Poll indicates that support for the taxes, which has held steady at around 55%, would collapse if the legislature authorized the HSR bond sale:

The unpopularity of the multi-billion dollar project appears to be negatively affecting chances of voters endorsing the Governor’s tax increase proposal should the legislature authorize funds to the project. Nearly one in three likely voters, including one in five voters who currently support the Governor’s initiative, say they’d be less inclined to vote Yes if the legislature begins funding the rail project.

This seems like a silly question, the idea that a legislative vote in July would have that deep an impact on a ballot initiative in November. But it may be enough to spook enough Democrats in the Senate, which has its share of moderates.

If you believe that America should have first-class infrastructure, if you believe in the benefits to productivity and reducing carbon emissions and creating an environment for economic growth in the nation’s largest state, if you believe that times of economic struggle are actually perfect moments for infrastructure improvements, while labor costs are relatively low (consider the other great wonder of California, the Golden Gate Bridge, built during the Depression), then tomorrow is an enormous test of that proposition.