He's a bellwether for the party. "How far can we push the message". That's not ironically the exact purposes of primaries when you get down to it - consolidating a party message. You use different politicians to highlight different aspects, send them out and get the feedback. They'll do it for healthcare platforms the same way they will for fascist ones. Same game rules apply.
Might seem kind of snarky to generalize actual states and actual people and their actual lives as game theory, but that's exactly what they do. Because it works. Every major party engages in that kind of thing worldwide.