Amazon.com Inc. is a company that is accustomed to winning, but the $869 billion e-commerce giant has spent the last few weeks suffering through humbling defeats. On Oct. 25, the Pentagon announced it was awarding a $10 billion cloud computing contract to Microsoft Corp. Amazon had been seen as such a prohibitive favorite for the contract, called JEDI, that the Department of Defense was actually facing a lawsuit for setting up a process that only the company could win. Then Amazon’s preferred candidates failed to capture control of the Seattle City Council in local elections less than two weeks later,