About as plausible as the polls showing Feingold blanching Johnson. Baldwin is favored, but she won't win by 14 in a state as polarized as WI.
Btw: This is gonna be the case in so many states. You'll see people like Donnelly, Manchin, Tester, Baldwin, etc. all opening out big leads in the polls, simply because it's early, their GOP challengers are not determined yet and polls in many of those states tend to have a pro-D bias. I doubt Republican polls in other states are showing a much better picture for the GOP.
+100. First Bayh - Young polls in 2016 immediately come to mind too...