When it comes to politics, I believe it's vital to try to understand perspectives other than your own. Al Jazeera's website in English is essential viewing for anyone interested in understanding the situation in the Middle East from an Arab perspective.
There's nothing like cold, hard facts to inform a political position. Open Secrets is Sponsored by the Center for Responsive Politics, a non-partisan research group that tracks money in politics and its effect on elections and public policy. Go here to find out exactly which organizations are financing your candidate.

Democracy Now! is a national, daily, independentradio program hosted by award-winning journalists Amy Goodman and Juan Gonzalez. Go to their website to listen to engaging coverage of politics on the home front and elsewhere. (You can also read the transcripts.) Thought-provoking and thorough.
The International Crisis Group is a non-governmental organization, dedicated to preventing and resolving deadly conflict around the world. Their reports are based on field research in countries where violent conflict is all too common. Go here for fascinating analysis of Iraq, Pakistan, Afghanistan – you name the conflict, ICG will lay out the facts and explain them.
Run by Berkman Center for Internet & Society at Harvard, Global Voices promotes citizen journalism around the world, aiming "to aggregate, curate, and amplify the global conversation online — shining light on places and people other media often ignore." The site features blogs about a variety of topics from developing countries worldwide. Go here to see politics from a new perspective.