Proponents of a local option sales tax have gained big ally in their legislative fight: Gov. Steve Beshear. The local option sales tax would allowcities to levy an additional tax on top of the state’s current six percent sales tax for specific projects, if local voters approved the new tax.Louisville Mayor Greg Fischer and Lexington Mayor Jim Gray are the chief advocates pushing the idea, arguing their cities would use the extra revenue for infrastructure projects.Speaking on Wednesday to the Louisville Chamber of Commerce, Beshear says he’s all for the idea.“Well you know politicians are famous for being on both sides of an issue so let me say this… I’m for it,” Beshear says.To go into effect, lawmakers would have to amend the state constitution and then statewide voters would have to approve the amendment. Local voters would have to approve each new local option tax at the ballot.State Sen. Kathy Stein, a Lexington Democrat, has alreadyfiled legislation to allow for a local option sales tax. The bill has been referred to committee, but its uncertain whether the bill will become law this session.Beshear says the idea is a no-brainer.“I mean, it just makes sense," he said. "Particularly if it’s structured to where, No. 1, once the local council or whoever decides what they want to do, then it’s submitted to a vote of the people."Supporters of the new tax say it would include sunset provisions, so that local communities wouldn't be indefinitely submitted to extra taxes for revenue.