The revelations that John Walsh plagiarized a major paper in college have now completely torpedoed his chances for retaining the seat. To be fair, there was little chance that Walsh was going to win in any case. But the difference between "little chance" and "no chance" can be measured in hope. There is now no hope for Democrats in Montana, this year.
Over the course of the next two months, the Tea Party movement may become to be seen (to mix a few metaphors) as more of a paper tiger than the tail that wags the Republican dog. To put it a little more concretely, the Tea Party may be losing some of its outsized influence over the Republican Party.
Congress is now doing what it normally does, in an election year. This is not intended to sound cynical, as I actually think it is a good thing for a divided Congress to stand up for its divided beliefs -- even while knowing that almost none of the bills it now votes on have a prayer of becoming law before the election.