BART proponents and opponents have been on the edge of their seats over the last few weeks, watching to see whether Measure B, the one-eighth-cent sales tax to help bring BART to Silicon Valley, will reach the two-thirds majority needed to pass. The measure didn't appear likely to pass last week, but this week it seems possible.

The county measure has been too close to call since the Nov. 4 election as provisional and absentee ballots were slowly counted and it was a few percentage points shy of the 66.67 percent required to pass.

On Monday, however, the vote count put it at exactly the required majority, in a surprise to many -- even the measure's supporters had been saying it was unlikely.

About 10,000 provisional and absentee ballots have yet to be counted. The final results are expected early next week, and will be made official on Dec. 4.

Measure B's possible loss had spurred transit leaders to talk about shortening the extension to make it more financially feasible, ending the line in San Jose's Berryessa neighborhood or Milpitas rather than running it underground through downtown San Jose.

The sales tax increase would provide $42 million a year to fund operations of the proposed $6 billion extension, but would not be imposed until federal funding is assured for the project. The transit agency hopes to use Measure B as proof that the project deserves an additional $750 million in federal funding for construction. The state has reportedly already committed $760 million.

Whether or not the measure passes, Phil Yost of Silicon Valley Leadership Group said the vote still indicates large support for BART.

"It may not quite meet the threshold for getting a tax, but it indicates a huge vote of support for BART," Yost said. "We hope the VTA board takes note of that."

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