Iowa Senator Tom Harkin won’t seek re-election

Iowa Sen. Tom Harkin said Saturday he planned to retire and would not seek re-election to a sixth term, opening up a seat Democrats have held for nearly 30 years.

First elected in 1984, the 73-year-old cited his age as a factor in the decision.

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He told The Associated Press it's time to let other Democrats step forward.

“It’s not easy to walk away, but life is fleeting,” Harkin said in an interview Saturday. “I’ve had the privilege to be here for 40 years. Too many people hang on to power for too long, and that’s not right.”

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The move surprised many given his war chest of nearly $3 million, The New York Times reported.

He's also hugely popular in Iowa and a major force in Congress with fellow Iowa Sen. Chuck Grassley, a Republican, according to the Des Moines Register.

Harkin's retirement presents the GOP an opportunity and a test, the Washington Post reported.

The party could go with a more moderate, electable Republican like Rep. Tom Latham, or take a risk with an outspoken, tea party favorite like Rep. Steve King, according to the Post.