Meanwhile, national Democrats are publicly denying any involvement but are privately flagging polls—albeit limited in number—suggesting Nebraska may be closer than any state with a 2-to-1 Republican voter registration advantage should be.

Republicans are looking to avoid a disaster in the Nebraska Senate race amid signs that an independent candidate could be giving Sen. Deb Fischer (R-Neb.) a run for her money. Independent Senate candidate and political newcomer Dan Osborn is challenging Fischer for her seat,

Independent Dan Osborn is running a surprisingly competitive Senate race in deep-red Nebraska in his bid to unseat two-term Sen. Deb Fischer.

These are the key Senate contests in Michigan, Ohio, Wisconsin, and seven other states that will determine whether Democrats keep control.