Greater sage grouse, an obscure bird known for its mating dance, could help seal Senate's fate

A little-known bird the size of a chicken could help determine which party controls the U.S. Senate next year.

The federal government will decide whether to list the greater sage grouse as an endangered species in 2015.

Such a listing could freeze development, ranching and hunting on hundreds of millions of acres in Western states.

Two Republican congressmen running for U.S. Senate in Montana and Colorado are backing legislation to prevent the federal government from protecting the bird.

The lawmakers want states to take the lead. Their Democratic opponents and environmentalists say that's a bad idea — but that states will only take the necessary steps to preserve the bird's habitat if there's the risk of federal protection.