Doesn’t really think he can separate his political involvement from his public health views.
Check it out:

Sen. Joe Manchin (D-W.Va.) is bucking Democratic leadership to vote against the controversial surgeon general nominee whom conservatives have bashed for calling gun violence a public health concern.

“I don’t believe it’s appropriate for America’s number one doctor to participate in political activism,” Manchin said in a statement Monday.

“I don’t question his medical qualifications; I just question whether the public will believe that he can separate his political beliefs from his public health views. I am wary that his past comments and political involvement will have an impact on his leadership capabilities and effectiveness,” Manchin added.