Harris actually sounds pretty good when she’s talking politics. Her tough on crime past can give her a boost with moderates and centrists as well. She just has the weirdest mannerisms when trying to relate to people.
Manchin has obvious appeal to centrists and moderates. His biggest issue is his opposition to climate change action. But other than that he’d be considered liberal by '90s standards.
Newsom needs to go through the primary process to see if he can appeal to swing state voters. Because I’m not convinced he can win those margin votes that he needs.