I wanted to add my thoughts on the current situation with Shelby. This isn't the first time he's pulled something like this, and it wont' be the last, I fear
Last summer, it came out that Senator Shelby was holding up the spending of money for NASA, from the stimulus bill. Basically, President Obama wanted to split the money intended for human spaceflight between Project Constellation, and Commercial Crew. Senator Shelby wanted it all for Project Constellation (and its worth noting that in Alabama is Marshall Spaceflight Center, who would be building the Ares I and Ares V). In the end most of the money went to Constellation.
Now, if you haven't heard about the Shelby hold, go look at the front page. But, I suspect the proposed earmarks aren't the only issue. As you've probably heard, President Obama canceled Project Constellation. He did not cancel human spaceflight, because ISS is still going to be around, and he instead wants to invest heavily in developing the private industry of space taxis (which, BTW, gets rid of the cost-plus contracts, and forces companies to actually deliver hardware for stated price).
The big loser in this budget is going to be Marshall, since Ares I is going away, and Ares V will never be done - Just to be clear - Marshall will still have stuff to do, but it'll lose importance. One person from the Obama administration effectively said that Senators have to stop treating NASA as their personal jobs program
And this brings us to Senator Shelby - he is fighting for his earmarks, but also so that he can have his vision forced on the President, for NASA. And his hypocrisy about this is well established, since he is all for private enterprise, except as it relates to space - then its a death march of human spaceflight.
Senator Shelby cannot be allowed to win