The best political insights and analysis I've EVER seen has been from a gentleman known as Billmon. He used to post to a site called Whiskey Bar, but hung up his cleats after getting burned out. I'm happy to say he's back - at least for the moment, posting to a diary at Daily Kos. I highly encourage you to take a look at his writing whenever it pops up.
If you doubt my absolute slavish blathering about this guy, before he pulled his website down some of his fans copied it and put it into an archive - you can peruse some of his writing skills and see what I'm talking about.