LAS VEGAS (AP) - Senate Democrats say Majority Leader Steven Horsford's decision to run for Congress won't cost them their control over Nevada's upper legislative chamber.

Horsford formally announced Thursday that he will run for a U.S. House seat.

Republicans praised Horsford's decision, saying the looming leadership vacuum will help them reclaim the Senate as planned.

Senate Democrats enjoy a slim 11-10 majority. They took control of the chamber for the first time in 18 years in 2008, and made Horsford their leader.

Senate Democrats executive director Michael Luce insists the Democrats have the candidates and experienced campaign staff to stay in power. Democrats are hoping to elect 12 of their candidates next year.

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