Our latest Senate simulation has the chamber convening in 2011 with an average of 53.4 Democrats (counting Joe Lieberman and Bernie Sanders), 46.1 Republicans, and 0.5 Charlie Crists. This is an improvement for Republicans from our last forecast three weeks ago, which had 55.2 Democrats, 44.2 Republicans, and 0.6 Crists. The changes, however, predominantly reflect several methodological improvements we have made rather than any particular national momentum, although the dynamics of some individual contests are certainly evolving.
The model gives Republicans a 17 percent chance of taking over the Senate if Charlie Crist caucuses with them, up significantly from 6 percent three weeks ago. If Crist does not caucus with them, their chances of a takeover are 12 percent. However, the model does not account for the contingency that someone like Joe Lieberman or Ben Nelson could decide to switch parties, which makes their chances slightly better than we suggest here.
Democrats' chances of gaining a net of one or more seat and re-claiming a 60-seat majority are 7 percent, down from 12 percent three weeks ago. If they could persuade Charlie Crist to caucus with them, however, their chances would improve to 10 percent.
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