I don’t expect a rout.
In 2012, we had a massive Democratic turnout and of course Obama was still popular enough despite his problems that he could comfortably win re-election.
As for the polls, the undecideds generally don’t make up their minds until the weekend before the election. In 2012, they broke for Obama.
This year, they seem to be going GOP.
Reasonable doubt. That's what the Democrats are doing to the voters. They're telling the voters that Republicans are going to cut this, war on women, in bed with corporations, etc. Republican candidates are playing defense and will co-opt many of the Democrat's statist goals. This in turns demoralizes the conservative base, and the swing voters will stay home or just vote for the Democrat.
I've been on this board for 15 years, and I know how this is going to play out to a tee. The Republicans are not going to win the Senate, the media will say they went "too far to the right," and the Karl Rove consultants will blame the Tea Party and fracture the party even more, and conservatives will be even more alienated and more infighting will ensue. All because Republicans can't just stick to their guns.