Yeah, I know. No one really cares what happens in flyover country.
Ben Nelson (D-NE) spent all of his accrued political capital as the swing vote for health care. I do not know if he will run again. The current State Attorney General Jon Bruning has announced his interest and will likely run unopposed for the Republican nomination. If so, he will likely win.
I seriously doubt it. Doing so would expose him to a Republican closed primary election. His chances are a lot better by remaining a Democrat. (And Dems hold the Senate by a sufficient majority that there won’t be any pleading or promises made to get him to switch.)