The different houses' take on the Senate race probabilities right now:
538: R+58.2% (updated yesterday)
NYTimes The Upshot: R +57% (updated yesterday)
WP Election Lab: R +54% (updated 3 days ago)
Daily Kos: R +53% (updated August 25?)
HuffPost Pollster: D +56% (last updated today)
Princeton Election Consortium: D +81% (updated today)
Also, Election Projection.com: 50-50 (
http://www.electionprojection.com/2014-elections/2014-senate-elections.php), meaning a slight Democratic majority
So according to these five election forecasters, it's just as likely for a Democratic majority as a Republican one. And not even one of them thinks the GOP chances of retaking the Senate is currently greater than 60%.