I don't know IceSpear. He's down 10 right now, in 2014, a Republican-friendly midterm year, in a Republican internal. He has the support of all the casino worker unions, and he even has the casino owners firmly in his pocket (or him in theirs), even Adelson to an extent. Hillary Clinton will be on the top of the ballot against God knows who...
This isn't the most unpopular Reid's been in the past decade.
You make good points, but if Angle can get 45% against Reid, I find it really hard to see how Sandoval can't get 50%. As for campaign contributions, Reid will be well funded, but so would Sandoval. People are going to shell out big bucks to take out Reid. Even Angle outraised him, and she was a complete nutjob.
If 2016 ends up being a good Democratic year (as it seems like it could be at the moment), it could end up barely dragging Reid over the finish line, but that wouldn't be his own doing.
There's also the "None of the above" option which could actually end up hurting Reid. Dean Heller and Mitt Romney got about the same percentage of the vote in 2012 (about 46%, I believe). However, Heller ended up winning because a bunch of Obama voters voted for None of the above and the fringe independent guy instead of Berkley.