Story highlights Former Iowa Sen. Tom Harkin endorses Clinton presidential bid in an op-ed piece

Harkin has been a longtime ally of both Bill and Hillary Clinton

Des Moines, Iowa (CNN) As Hillary Clinton arrives in the Hawkeye State for a weekend packed with a town hall, a speech at the Wing Ding Dinner and a visit to the Iowa State Fair, she's picked up a key endorsement from a beloved voice in the Iowa Democratic party.

Former Iowa Sen. Tom Harkin endorsed Hillary Clinton's candidacy in a Des Moines Register op-ed published online Thursday night.

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"As Democrats, we're fortunate to have a slate of candidates that are all fine individuals, but we need a fighter who has a record of getting things done and the vision for the future that will build on the progress we've made. For my wife, Ruth and I, that candidate is Hillary Clinton," Harkin wrote.

Harkin praised Clinton's "commitment to public service," her advocacy of women and families, and her dedication to "the idea of expanding opportunity."

Harkin ran for president himself in 1992 and has been a longtime ally of the Clintons.

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