DENVER (AP) -- Supporters of same-sex civil union legislation are trying to unseat a Republican lawmaker whose narrow victory two years ago gave the GOP control of the Colorado House and the fate of the proposal.

A group called "Fight Back Colorado" announced Tuesday that Jefferson County Rep. Robert Ramirez will be the first lawmaker whose district receives attack mailers. The group formed to try to defeat Republicans who oppose civil unions and will announce other lawmakers they'll target in the coming weeks.

Ramirez never voted on the legislation. He says he supports strengthening gay rights, but that the civil unions bill resembled marriage too much.

Ramirez defeated a Democrat by 197 votes in 2010. The victory gave Republicans a 33-32 edge in the House and the leverage to stop civil unions the last two years.

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