Story highlights Former Michigan Gov. William Milliken, a Republican, is supporting Hillary Clinton

He cited the need for "tolerance, civility and equality" in the 2016 campaign

Washington (CNN) A former Republican governor of Michigan is breaking with his party to endorse Hillary Clinton, as both she and Donald Trump head there this week to lay out their economic plans.

Former Gov. William Milliken, who served from 1969 to 1983, cited the need for "tolerance, civility and equality" in his decision.

"We face a critically important choice in this year's presidential election that will define whether we maintain our commitment to those ideals or embark on a path that has doomed other governments and nations throughout history," Milliken said in a statement Monday backing the Democratic nominee.

"I am saddened and dismayed that the Republican Party this year has nominated a candidate who has repeatedly demonstrated that he does not embrace those ideals. Because I feel so strongly about our nation's future, I will be joining the growing list of former and present government officials in casting my vote for Hillary Clinton for president in 2016."

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