LAS VEGAS (AP) - A key Nevada election with implications for control of the U.S. Senate will reach an end when voters decide the race between Republican Dean Heller and Democrat Shelley Berkley.

Voters on Tuesday also will decide bitterly fought House battles in the 3rd District between Republican Congressman Joe Heck and Democrat John Oceguera (oh-see-GEHR'-ah), and in the new 4th District between Republican Danny Tarkanian (tar-KAY'-nee-uhn) and Democrat Steven Horsford.

Early on Tarkanian was considered a longshot after three previous unsuccessful runs for elected office. But he's led in recent polls.

Republican Congressman Mark Amodei (AH'-muh-day) is facing a challenge from Democrat Samuel Koepnick (KOH'-pnik) in the 2nd District.

Former Democratic Congresswoman Dina Titus is seeking a return to Congress in her 1st District race against GOP former Navy officer Christopher Edwards.

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