What do I do about this internship?

So here’s the situation.

I will be graduating this upcoming May from university. As of now, while I have work experience, it is not experience in my field (I’ve worked as a secretary, cashier, etc). So, a few months ago I went on an internship application frenzy and applied for multiple jobs that were at least related to my field. I received an email from one of them a couple of weeks ago for a phone interview. It wasn’t like my favorite company or anything but work is work so of course I said yes. Just received an email earlier today from the company (non profit) saying that they want to hire me and they want me to start working the second week of January. Normally, I would be ecstatic, but there is a problem. The number one company I want to intern for is a major television network. I did a tour of the place last week and was able to actually talk to the people that I would directly be working with if I was chosen. Got some emails, networked, and I think they like me. I found out though that they don’t even choose people for their Spring program until the second week of January. Basically, I won’t even know if I got that internship until AFTER I’m supposed to start the other one. What do I do? I need work experience; the last thing I want to happen is that I accept the job and then I hear that the TV network wants me and I can’t accept. But then at the same time, I don’t want to turn down the internship with the non-profit company only to find out that I didn’t get the job with the TV network either. The non profit wants a response. What do I do?