UPDATE 1-US Senate raises roadblock to biodiesel tax credit

* New version of tax bill expected soon

* Biodiesel output slumps to low level

* Biodiesel takes 11 pct of US soyoil (Updates with status of new version of bill, biodiesel board comment)

WASHINGTON, June 16 (Reuters) - Revival of a $1 per gallon biodiesel tax credit stalled on Wednesday after a U.S. Senate procedural vote derailed a $126 billion tax bill, but an industry source expected a newer version of the bill to include the tax credit.

Finance Committee Chairman Max Baucus was expected to offer a less-costly substitute to the bill that would reduce Medicare spending. A Baucus aide did not respond to questions about the possible survival of the biodiesel credit, a popular cause in many farm states.

The new version of the bill was expected to be unveiled later on Wednesday.

A spokesman for the National Biodiesel Board, a trade group, said it appeared the biodiesel credit would be retained. "There's been no objection to it," said the spokesman.

Biodiesel production may drop to 15 percent of capacity because of loss of the credit, said the trade group.

The Agriculture Department has estimated that 11 percent, or 2.2 billion pounds, of U.S.-produced soybean oil will be used this marketing year to make biodiesel. The green alternative to diesel oil is produced in 44 states.

The biodiesel tax credit expired at the end of 2009. The House and Senate have voted in recent months for a one-year revival, retroactive to Jan. 1, but as part of differing bills. They must agree on a text before the revival can become law. (Reporting by Charles Abbott; Editing by David Gregorio)