Solve the federal budget deficit
The NY Times has published a fun interactive graphic that lets you do what Congress and the President have not been able to manage: balancing the federal budget.
Try your hand at it:
http://www.nytimes.com/interactive/2010/11/13/weekinreview/deficits-graphic.html
Then email it to the candidates for U.S. Senate and ask them to fill it out. Any that refuse to reveal their preferences don't deserve serious consideration.