Hoping to sway lawmakers, two of the state's most famous residents and one of its former governors joined groups opposed to the Vermont Yankee nuclear power plant on Thursday in announcing a push for Town Meeting Day votes on whether the plant should keep operating past 2012.

Ice cream icons Ben Cohen and Jerry Greenfield and former Gov. Phil Hoff lent their voices to those who want the Legislature to turn thumbs down on Vermont Yankee's request for a 20-year license extension.

Cohen, who's from Williston, said the nuclear power plant flies in the face of the state's image as having a pure environment. He said an accident at the aging plant could destroy lives, property and the local economy.

"The economy, the tourism economy and the wonderful image, the wonderful halo it's created for a whole raft of food products, is all based on the image of the purity of the environment in Vermont," Cohen said.

The plant, which opened in 1972, has endured in recent years a series of mishaps that have prompted calls for its closure.

Plant officials and other proponents, however, contend that it offers reliable "emission-free" power generation and that its power helps keep electricity rates down.

Typically, nuclear plant regulation falls to the federal government, through the U.S. Nuclear Regulatory Commission.

Vermont is the only state that has reserved say-so for license extensions, so the battle for Vermont Yankee is in the Legislature, which could vote on it in the session that begins in January.

While Town Meeting Day votes on it would be only advisory in nature, Vermont Yankee opponents see them as a tool to persuade lawmakers to vote no when the relicensing comes to a vote in Montpelier. Last year, 36 towns approved anti-Vermont Yankee resolutions; two rejected them.

South Burlington attorney James Leas, one of the organizers of the effort against the plant, said the goal is to get the scores of towns that didn't vote last year to do so on Town Meeting Day, which falls March 2.

Cohen called Vermont Yankee a threat to the state's clean-and-green image, which helped Ben & Jerry's Homemade Ice Cream succeed. A major accident at the plant could ruin it, he said.

Hoff, a Democrat who served from 1963 to 1969, said the power of Vermont lies in its people, and he said grass-roots opposition was the key to closing Vermont Yankee.

State lawmakers say they need to know how much Vermont Yankee will charge for its power before voting on whether to renew its license. They set a Nov. 1 deadline by which Vermont Yankee was to reach new power purchase agreements with utilities Green Mountain Power Corp. and Central Vermont Public Service Corp., but the deadline passed.

The plant owners now hope to reach power purchase agreements by Dec. 18, and if they don't they will present an offer to the state Public Service Board anyway, Vermont Yankee communications manager Larry Smith said.

Smith touted the nuclear power plant's 650 full-time jobs and the $100 million it helps contribute to the state economy.

"We continue to stress there is tremendous economic benefit for continued operation of Vermont Yankee," he said. "We feel we have a good story to tell the people of Vermont and the Legislature."