As you can see in the graph below, the GOP's chances have now risen essentially every day for the past week (save for a small drop of 1% on one day). With a 66.2% chance of the GOP winning, the race for the majority in the Senate can no longer be considered a tossup. Sure, a couple races are still tossups, which is why there is still a fair amount of uncertainty in the forecast. But at this point, Democrats need for things to begin breaking their way.
This is not all to say that Republicans will for sure win the Senate. In fact, I wrote earlier today about how that storyline is premature and currently false. But the GOP will be odds-on favorites to win on election night if the rate of their increase in probability remains steady. Assuming that were the case, Republicans would have a 91% chance of winning on election night.
So what happened today that drove the nearly 3% increase in the party's fortunes? Two polls each told the same story in New Hampshire, where Senator Jeanne Shaheen is now running in a closer-than-expected re-election battle. The polls each had Shaheen beating Scott Brown by three points. That's about in-line with the average now of the polls, giving the Senator a 68% chance of winning in two weeks.
There was also a PPP poll of North Carolina, showing the Democrat, Kay Hagan, up by three points. Tillis has still yet to lead in a single polls since the summer (he has tied in one), and Hagan's fortunes remained about the same with the inclusion of this new poll.
Finally, SurveyUSA polled Kentucky voters and found Alison Lundergan Grimes to be slipping relative to their last poll two weeks ago. The prior poll had Grimes up by two, and the newest one has her trailing by one. Each of these is within the margin of error, but when combined with other polls of the state, Grimes is the clear underdog. She now has only a 20% chance of winning, down from 25% just yesterday.