In my earlier post "Candidates Respond on Bailout", I included a quote from Senator Obama on his intention to reduce government spending on private contractors by 10%. I found an analysis of the bills and amendments sponsored by both Senator McCain and Senator Obama over the past four years that help depict how Senator Obama may do just that.
Several times over his tenure as a US Senator, Obama has sponsored amendments to bills that would proscribe large contracts from being issued using "procedures other than competitive procedures." These types of contract awarding procedures will make sure that the federal government hires contractors at a competitive rate, instead of the no-bid contracts that, frankly, do not make sense.
If you were going to have the roof of your home replaced or perform a major remodel totaling several thousand dollars, you would of course get multiple estimates from different contractors, likely after asking folks you trust for references. Why would the government spend 1000 times that amount or more on a contract that they hadn't done similar comparisons on? If the answer is just "expedience," that's not good enough. Our government needs to do the most with the money it collects from us, and that entails getting the best deal for the buck.
The Washington Monthly link below lists off numerous other legislative accomplishments of both senators and is well worth reading.
 Political Animal: Compare and Contrast