I don’t think there’s anything particularly partisan about the law in the first place so it’s not so much an issue of what any party supports but rather education of the electorate at large. People aren’t going to get excited about encryption but they will be angry when WhatsApp stops working (which is what is going to happen) and they need to know why. Ideally they’ll hear enough rumblings that literally all of their messaging apps are going to stop working before the law goes into effect to stop it in time.