According to Politio: 

Sen. Orrin Hatch (R-Utah), the longest-serving Republican senator, announced Tuesday he will retire at the end of the year. The move opens the door to a likely run for the Utah seat by former GOP presidential nominee Mitt Romney.

“Every good fighter knows when to hang up the gloves. And for me, that time is soon approaching,” said the 83-year-old senator, who was first elected in 1976, in a video announcement. “That’s why after much prayer and discussion with family and friends, I’ve decided to retire at the end of this term.”

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