Yes, indeed. But, IMO, it wasn't the end of the contest:

As a member of the Senate subcommittee grilling Michael, Geary had to know that the FBI was holding Pentangeli in secret, and that the subcommittee would drop him on Michael. But he didn't tell Michael or Tom.

I also believe Geary helped set up Michael during Cicci's testimony. He asks Cicci: "Did you ever get an order directly from Michael Corleone? Or was there always a buffer?" While this seemed helpful to Michael, I believe it was a setup: Since Michael thought Pentangeli was dead, he thought Cicci was the highest-ranking witness the subcommittee could call. And since Cicci, thanks to Geary's prompting, said he never talked to Michael, he thought it was safe for him to perjure himself.

Finally, that little speech Geary made about Italian Americans being "the salt of the earth," could have been two-faced. When he said "...these hearings on the Mafia," who did he mean if not the biggest Mafioso sitting in the witness chair? And when he said "It'd be a shame, Mr. Chairman, for a few rotten apples to spoil the whole bunch," who did he mean if not the rotten apple in the witness chair?