There has been a fair amount of speculation about whether or not the Democrats would allow Sen. Joe Lieberman to caucus with them next year. With the Senate currently being split 51 - 49, Lieberman's membership in the Democratic caucus this year has allowed the party to achieve majority status. Nonetheless, the number of Democrats in the Senate is likely to increase after the elections in November and their majority status will no longer depend upon Lieberman's presence. With that it mind it appears as though there is the possibility of kicking him out of the caucus if he follows through with his scheduled speech at the Republican National Convention.
On the other hand, members of the Democratic leadership who won't even publicly admit they're considering removing Lieberman from his position as chairman of the Homeland Security and Governmental Affairs Committee. The Hill, for instance, pointed out that Harry Reid insists they are focusing on this year and trying to pass legislation with the majority that they currently have. This very well might be true, especially since Reid's statements seemed to suggest he simply didn't want to create a stir when they only have a fragile majority and an election is rapidly approaching. However, it also says that the leadership is not 100% behind removing Lieberman from his post. If they were, then it's unlikely Reid would be so desperately trying to avoid the issue.
Since the main point of division between Lieberman and the rest of the Democratic caucus is his stance on homeland security issues and the war in Iraq, it seems to me like removing him from his chairmanship would be the right decision to make. Replacing him with another expert on homeland security who actually agrees with the Democrats would allow the committee to fully pursue options relating to homeland security that they truly believe will be beneficial.
Since the leadership won't even commit to taking this action, however, I find it rather unlikely that they would actually go even further and kick Lieberman out of the caucus altogether.The road I see being used is that the leadership will strip Lieberman of his chairmanship, but will avoid having it be an issue during the election by not making the announcement until after November. Once the decision has been made to remove him from his post on the Homeland Security and Governmental Affairs Committee has been made, the Democratic leadership will then give Lieberman the option of staying in the Democratic caucus if he so desires. His decision will depend on who's president. If it's Obama he'll caucus with the Democrats and if it's McCain he'll caucus with the Republicans.