No.
Even if what you describe is true, that does not make them “sociopaths.” You could argue that as representatives of their constituents, it is both natural and appropriate that they should defer to their opinions over their personal beliefs, even if they are motivated to do so by self-preservation. I’m not saying I necessarily agree with that, by the way. But I do think it is human nature to fight for your self-preservation, and that it is necessary to be effective in politics to sometimes make compromises and pick your battles over just constantly grandstanding for whatever you believe in. That doesn’t mean you don’t believe in anything, let alone that you are a sociopath. It just makes you a pragmatist and realist. That doesn’t mean there aren’t some truly shameless politicians who take hypocrisy and cynicism to another level (ahem, Lindsey Graham). But even still, “sociopath” is a strong word and I hesitate to use it in most cases.
So you don’t think it’s a bit sociopathic to vote for something you know would damage the country just for the sake of having a higher chance of being re-elected? How about the 2/3rds of Republicans in the House who voted against certifying the election, even though they know Biden won fairly, just for the sake of having a less serious primary challenge?