In the 2000 election, immediately after the Supreme Court decision, speculation was rampant as to why the 5 justices violated their own "States' Rights" mantra by stepping in on a case that Florida law could easily have handled independently. Obviously their egregious violation of principle was motivated by a desire for a Bush victory.
The obvious answer at the time was retirements. O'Connor and Rehnquist, especially, were rumored to be near retirement. O'Connor, IIRC, had been overheard commenting before the election that she hoped Bush would win so she could retire with peace of mind, knowing she'd be replaced by a Republican.
So why haven't any of them retired? Have the retirement-eligible justices realized the error of Bush's ways? I don't think Rehnquist is even capable of questioning this administration, But that doesn't explain why hasn't he stepped down to usher in the era of Chief Justice Scalia. O'Connor may have gotten disgusted real early, and resolved to hold on for another 4 years. How else to explain why the independent/paleoconservative who was so looking forward to retiring is still around 4 years later?
Maybe they were never planning on retirement in the first place. If that is the reason, why the flagrant violation of their own precedent in the decision? Why the imperious hijacking of a state's democratic election? What did they have to gain?