As of right now, Ken Buck has a 10K lead on Michael Bennet. However, a closer look at the numbers indicates that Senator Bennet is sitting pretty.
95% of El Paso County is in-this is Colorado Springs, home of the Christian Right. At the same time, Denver and Boulder are about 50-60% in, and Bennet is sure to pick up tens of thousands of votes when the remaining votes here are counted. Extrapolating the current totals (which is a bit crude, but reasonably predictive) indicates that Bennet should pick up at least 70K in these two areas alone.
If you add Patty Murray to Senator Bennet, we'd get to 53 Senate seats. This would be a pretty solid performance, and would at least partially cancel out the bloodbath in the House. We wouldn't have to worry about Holy Joe and Ben Nelson tipping the balance of power.