Apparently you can. I just did it yesterday.
According to TSA, the protocol of flying without ID is: 1) prepare to answer a few identity related questions; 2) go through enhanced security screening. Chicago O’Hare airport followed the protocol very well. The whole process took about 25 minutes due to the lengthy process of verifying my identify through the antiquated phone system with the supervisor relying my answers to the hearing impaired phone operator. Afterward the supervisor apologized for the delay but of course I genuinely thanked him.
Privacy expert Chris Soghoian challenged the ID requirement in 2007 that got TSA to clarify the flying without ID protocol. I met Dr. Soghoian for the first time this year at an FTC event. He is a very nice young man and currently employed by FTC for consumer privacy protection. For fear of defiance and rebellious behavior, TSA further clarified its position in 2008 that would allow TSA operators ban access to people who are not cooperative. Since I lost my ID by accident and cooperated fully with the TSA operators, I wouldn’t fall into that category.
So don’t panic next time if you lost your ID. You can still fly safely home as long as you get to the airport with plenty of time to spare.