Around six months ago, when speculation raged that Senator Joe Manchin might join a third-party presidential ticket on behalf of the centrist group No Labels, he privately consulted with Richard Gephardt, the former congressman who has taken up the cause of stopping No Labels in its tracks. Gephardt showed Manchin private polling that he’d bankrolled himself, illustrating that such a bid could only help Donald Trump beat President Biden, according to a person familiar with the conversation. Geph