No. Sports betting is not legal in Nebraska and while there are bills in the works to change that, it is a long way from happening in 2020.
The most recent bill introduced early 2020 would legalize sports betting, fantasy sports and poker, classifying them as skill-based games. It was already a long shot to pass and the Coronavirus pandemic won't help the process move along.
A main issue is that Nebraska doesn't even allow full-fledged casinos with table games and more than a few slots. Given that law, it'd be surprising if sports betting was legalized before 2021. While efforts have been made, new legislation has been difficult to pass, which means Nebraska residents will continue to flock outside the state to legally bet on sports.
For now, Nebraskans are limited to Daily Fantasy Sports and "games of skill." The state has yet to pass a law to confirm the legality of fantasy sports and set up regulations, but unlike sports betting, they aren't considered illegal which is why sites like DraftKings and FanDuel continue to operate.