While this isn't a regular day that I update my model, I made some changes and I wanted to post the results.
I added three new states to the model's statistics: Georgia, Kentucky, and Michigan. While these didn't really have any effect on the outcome, periodically there are political reports that discuss these three states. I guess you could say that I added them to the SanityIID Senate model just to be sure I wasn't missing anything.
Secondly, I made a change to the number of Monte Carlo iterations that the model performs. I originally didn't want to do this since it can give the impression of having more confidence in the model than the underlying numbers would justify; but on the other hand, it does keep the probabilities from swinging too far without any underlying polling behind the number.
Here is the histogram from the last run using the data from September 24, 2014: