A coalition made up of unions, teachers, environmentalists and minority activists urged lawmakers to slow their consideration of the unprecedented package.

The groups join in the excitement surrounding Tesla's plans, but their enthusiasm is tempered by many questions about the deal brokered in secret with the California-based company, said Bob Fulkerson, state director for the Progressive Leadership Alliance of Nevada.

The governor's plan leaves the door open to other corporations to "come feed at the tax-break trough," Fulkerson wrote Wednesday in an open letter to legislators. "While some subsidies may be warranted, the deal on the table appears far too generous, and far too risky."

Outside, backers of a Nevada film tax credit that would be gutted to help pay for unprecedented tax breaks for Tesla Motors protested with signs that read, "Keep Nevada Film Alive," and "Movie Industry Jobs Are Now."

Majority Democrats in the Senate and Assembly intended to open the session Wednesday to begin work on the package the Republican governor says would help further diversify Nevada's hard-hit, tourism-based economy through new and innovative technology.

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