Political Communications to land lines are generally exempt from do not call. Cellular communications require prior consent, but the “consent” could be as flimsy as being registered with a certain party. You must be able to opt-out from the communication, and that’s why they have the “reply stop” verbiage. If they don’t honor your request, you should report it. Failing to actually make an effort to stop the communication (as is strangely being suggested) should be the only reason you would continue to receive them.
The direct affiliation with a party or campaign is not a requirement.