The Clinton voters could not believe that all of the Nebraska delegates voted to align with Barack Obama even before the primary vote and some delegates aligned with Barack Obama even before the caucus vote held in early February, 2008.
If Illinois had not moved its primary date by SEVEN WEEKS from the end of March, 2008 to the beginning of February, 2008, the close to a dozen caucuses held shortly after the Illinois vote (which gave Obama a huge delegate push) would have not been able to use the excuse that Barack Obama was leading to vote for him. Factor in that Michigan was not counted at all, and Barack Obama definitely would have been trailing going into the caucus contests.
It is my opinion that Barack Obama's side funneled promises or money to the Great Plains Indians tribes in various states in exchange for their caucus votes. While some may view this as a shrewd move, it may not have been an ethical one as Politicians cannot directly promise government funds in exchange for their votes. Barack Obama has doled out huge lawsuit based awards to both Indian Tribes and African American farmers.
To Barack Obama's credit, he did visit Nebraska once whereas Hillary Clinton did not.