Which ML algorithm should I use for Classifying Tweets by Category?

Hi,

I have 1 million tweets that I would like to classify by category(i.e. music, movies, spam, etc - there will be 5 categories). What's a good first-cut algorithm to use? I am looking for 80%+ accuracy, so something easier to implement and tweak would be more preferable to the state of the art black-box.

I work in Python, so any good examples/tutorials or useful links are welcome. :)

Thanks!