He hasn't had to spend dime one of his own money.
Getting the amateurish birther lawsuits (can you say “Orly Taitz”?) dismissed has not been a huge expenditure of time or legal effort.
Asking why he didn't release it earlier is like asking why Hannibal didn't spring his ambush on the Romans.... until after they marched into it.
The idea that he spent millions of dollars is based upon some shoddy research to begin with, but has become an article of faith among many a birther.
http://www.theobamafile.com/_associates/RobertBauer.htm#disbursementsperkinscoie
I love it when you Obots make a public fool of yourself.