I'm sorry, but so-called "centrists," or "moderates," or Independents such as Lieberman and his best buddy, John McCain (yes, I realize that McCain has never professed to be an Independent), are not "mavericks" or "centrists" or Independents in any sense of those words. Instead, they are just typical politicians -- just like their brethren on the far left and far right -- in that they will do and say whatever is in their best political interests irregardless of what they may actually believe.
We've seen this on full display in Arizona in recent weeks, with McCain (facing a re-election primary challenge from a far-right conservative) disgustingly trying to appeal to the ultra-far-right and trying to distance himself from the "maverick" moniker that he only so willingly embraced over the past 10 years when it was in his best political interests to do so. And we see it too today from Lieberman, who promises to keep his options fully open as to whether he will run for re-election as an Independent, a dem or a repub. These men are not heroes of mine, I can tell you that (I voted for neither Obama nor McCain in 2008, for the record). As expressed, they're just typical.