WASHINGTON (AP) — Republican Sen. Dan Coats says he will retire from the U.S. Senate and won't seek re-election in 2016.

Coats, 71, a former ambassador to Germany, was serving his second full six-year term in the Senate representing the Midwest state of Indiana.

He says that it wasn't an easy decision but that he's concluded the time has come to pass the job to a new generation of leaders.

Republicans would be strongly favored to hang onto his seat.

Coats is a solid conservative who focused on budgetary and fiscal issues in the Senate. His announcement opens the way for what could be a lively Republican primary to replace him, with several House members and the mayor of Indianapolis among the potential candidates.

He becomes the third senator to announce plans to retire rather than seek re-election. The others are Democrats Barbara Boxer of California and Barbara Mikulski of Maryland.

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