Both sides expect that Carl Levin will, later this week or next, reintroduce an amendment that would strip F-22 funding from the Senate's defense authorization bill, but so far, despite support from both the administration and Senator McCain, Levin has been unable to corral enough votes to strip the money out. I emailed one senior Senate aide and asked what he made of this latest development. Here was his response:
The key point on this issue is to me that 187 provides you with just enough for seven thinned-out squadrons that have no backup aircraft inventory or attrition reserve. BAI and AR are essential, given the eventuallity of crashes or combat losses in aircraft squadrons over the Raptor's operational lifetime. This means that we have nowhere to go but down -- either further thinning out our squadrons, or simply closing them. With barely enough aircraft to fill out the force, it will be difficult if not impossible to sustain it.
If you look at Maj Gen Mark Gibson's statement to the Airland Subcommittee on June 9 that 187 is "higher risk," especially from the perspective of operations and sustainment, I believe that is the challenge he was speaking to.
Turning to your specific question, it seems that the effort to cut the F-22s has run into real Congressional concerns about these issues, which has been fueled by the ambivalence of Air Force testimony and other communications to Congress this year.
AEI's Michael Auslin also has a good piece on the numbers here.