I've met candidates who care. I've campaigned for them. But they're unlikely to be the heavy fundraisers or the ones close with the governor/legislative leadership.

I've been on the other side, too, and watched the more machine style politicians operate. A heavy focus on fundraising. The candidate is constantly courting local mega-donors and hosting/attending events. Your roll as a campaign worker is a lot like the roll of an MLM organizer - everyone is trying to recruit everyone else and your position in the hierarchy is heavily predicated on how much money/how many volunteers you can bring into the organization.

There are certainly true believers running for office. But they're just the bottom rung of the patronage network. Only as useful as they are freely loyal. As soon as they start showing independence or asking for more than their position affords them, they're targeted for a primary by a less demanding party acolyte.