I’ve been a Republican since 1980 but I’m voting for Hillary Clinton

As a young, first-time voter in 1972, I went with the Democrats. Then, after I began working for Mitt Romney at Bain & Company, and paying high state and federal income taxes, I started voting Republican for president in 1980. Since 1980, I've voted Republican every time except one.

With Mitt Romney as my first boss and mentor, and knowing well his extraordinary capabilities, I volunteered to be one of his eight original national finance chairs in 2006, working with my friend Meg Whitman.

For the next six years I worked hard on Mitt's campaigns and helped build a team which raised a record amount of money for him.

"Trump is the most dangerous major party presidential candidate in my lifetime, maybe in American history."

This year, however, watching and listening to Donald Trump's erratic daily bullying, ranting, bragging, scapegoating, and name-calling, my conscience and my three adult children will not let me vote for him.

Trump is the most dangerous major party presidential candidate in my lifetime, maybe in American history. His character, temperament, and behavior definitely are not presidential. I don't think he's fit to be our president. He speaks positively about foreign dictators and acts like one himself.

For decades, candidates, including successful business people, have released their tax returns; why does Trump think he shouldn't follow the rules of the game? Defeating him has to be our national priority.

For these reasons, I have decided to endorse and support Hillary Clinton for president, even though everybody else I will vote for this November will be a real Republican. Hillary Clinton knows her stuff. She is emotionally mature and centered. She respects and enjoys working with people from all backgrounds. She has the diplomatic skills needed to break the gridlock in Washington and lead our country well. America needs a steady hand on the tiller.

We cannot afford the risk of a man whose temperament and behavior are erratic.

Commentary by David Nierenberg, the president of Nierenberg Investment Management in Camas, Wash.

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