There has been much discussion about whether votes in this next election will be counted securely.
Every state has rules about what poll observers can do at the polls and how votes can be challenged. Here are the rules for your state:
Nebraska N/A Any person offering to vote, even though such person is registered, may be challenged as unqualified by any inspector, judge or clerk of election, or registered voter. The judge or clerk of election shall challenge any person offering to vote whom he or she knows or suspects not to be duly qualified. (Neb. Rev. Stat. § 32-926)