(Fox News) In his new memoir, former Vice President Joe Biden says he knew he was capable of beating Hillary Clinton in the Democratic primary, but he decided not to run for fear of a “stop at nothing” campaign by her backers.

“My numbers on trustworthiness, honesty, and empathy were as high as they had ever been. And I was strongest where the most formidable candidate, Hillary Clinton, was weakest: the key swing states like Pennsylvania, Ohio, and Florida,” Biden writes in “Promise Me, Dad: A Year of Hope, Hardship, and Purpose.”

He says that as the primary race was gearing up, he was still grieving his son Beau’s death. Although Biden does not mention it in his book, his family was also dealing with his other son Hunter’s messy divorce.

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