As a podcaster you need to be obsessed with your brand. But you can never take it for granted. Just because you've been successful in the past, doesn't mean that you can say or do anything you please. The United State's business history is littered with companies who have jumped the Branding Shark. Coca cola, General Motors, Ford, IBM and the list goes on and on. Bigger companies may have the ability to reverse their mistake, but for smaller entities - such as podcasters - this move can be fatal. Here's rule that you can safely live by. Unless your podcast is about politics, don't ever talk about it. The only thing you'll succeed in doing is self-immolation. Look at what's going on in the NFL today. Where you stand politically is completely besides the point. You have nothing to gain and 50 percent of your audience to lose. Is the risk worth the reward? I don't think so and neither should you. You have nothing to lose except your business. If you want to start a seperate podcast to highlight your political viewpoint, then go right ahead. Just don't taint your existing show with extraneous matters. If you have a healthy eating podcast and you start talking sports, the net result will be the same - lost listeners. Unless of course you're talking about dining options at sporting events.
You've invested so much time, effort and money into building your brand, why risk throwing it away?