I don't get this Atlas meme that a challenger should be embarrassed if they lose to an incumbent. Incumbents win more than 9 times out of 10 in most election years.
Nevada is one state that seems to keep their Senate incumbents running for reelection. How many times was Harry Reid "doomed," but managed to hold onto his seat? There's zero shocks here if Heller holds on and Rosen has nothing to be embarrassed about if she loses.
What the hell? Incumbents win 9 times out of 10 because 8 times out of 10 they don't face a serious challenge. For every Heller, there's a Tom Carper or Sheldon Whitehouse or Deb Fischer or John Barrasso.
This is a competitive election, and a candidate who loses a competitive election should take stock of their own flaws. Don't act like all incumbents are made equally.