Insufficient financial support has prompted Mark Olmstead to quit an effort to overturn Colorado's gay marriage ban.

Voters in the state approved a constitutional amendment that defines marriage as a heterosexual union in 2006.

In July, the 3-member board charged with approving proposed ballot questions voted unanimously in favor of Olmstead's proposed question for the 2012 ballot. To secure a spot on the 2012 ballot, proponents needed to collect roughly 86,000 signatures by January.

Olmstead, 19, a political science student at Seattle University, said he decided to withdraw his initiative after no organization stepped forward to fund the campaign.

“I realized this would be a very costly and time consuming campaign,” Olmstead told gay weekly Out Front Colorado. “It would be very difficult to pull off by myself.”

“I'm still going to be fighting for [marriage equality],” he added. “Maybe in a different way. A ballot initiative is just so hard to pull off.”

A civil unions bill, which was sponsored by gay Denver Democrats Rep. Mark Ferrandino and Senator Pat Steadman, died in a House committee earlier this year after passage in the Senate.