I have my own personal little conspiracy theory.

Let's say that Bush really intends to replace Rumsfield, as if to show the appearance of accountability now that the war has traction.  There is probably no way to replace him with a Democratic majority Senate.  And replacing Rumsfield before the election would not work to the White House's advantage.  

So, say we win the Senate and it is 51-49 and Joe has won his seat.  All the White House has to do is tap Joe Lieberman to be the next Secretary of Defense and how many of his old buddies will vote against him?  And in addition, the Republicans get back the Senate because Governor Rell will nominate a Republican who will  serve until a Republican Senate is no longer a problem for Bush. What say ye?

Even if this isn't the plan, it's certainly enough to worry people in Connecticut and could pen Lieberman into something of a corner.  I'm pretty sure that a large number of Independents in Connecticut would be distressed at the idea of a Republic Senator.  And there is precedence for Joe not caring about whether the Democrats retain the seat from 2000 when he ran for Senate and Vice President.