I'm not. But do you think they'd still have that incumbent advantage if they consistently voted against their party's interests (I should also clarify that with "and were honest about it, not lying through their teeth and claiming otherwise").

And even then, they wouldn't keep getting major donor funding if they weren't voting in those people's interests, incumbent or no.

Everyone thinks their senators are working for them. It's just the other 98 that's they disapprove of :D