“He is a decent, honorable man,” former Vice President Joseph R. Biden Jr. said in a recent interview of Mr. Romney. Mr. Biden conceded that it was unlikely that he would be running for president right now if it were Mr. Romney seeking re-election, not Mr. Trump. “I think this is Senator Romney’s moment to shine,” said Senator Amy Klobuchar... . . . “As Mitt once said in some context, ‘The worst thing that could happen to anyone in politics has already happened to me. I lost the presidency.’ It’s like the guys in Vietnam said, ‘What are you going...