I have worked for the airlines for 10 years. You are supposed to have a government issued ID, yes, but unfortunately people lose their wallets, have them stolen etc. In every airport I've worked in they would make exceptions for this. The TSA will just be extra thorough. They like it if you have something else with your name on it.
You are suppose to have a government issues picture id. Best to contact your airline.
I didn't think you could. Learned something from the above answer.
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