The question in Nebraska — as it is in other heavily Republican swaths of the country — isn’t if a Republican must be supportive of Trump to win an open statewide office. They almost certainly must be. It’s whether just supporting Trump is good enough — or if, in the reddest of states in the new GOP, only the Trumpiest candidate can win. In Nebraska, that means whether any institutionalist Republican — even a pro-Trump one — can beat Charles Herbster, the wealthy rancher and friend of Trump who not only supported him, but went so far as to attend the Jan. 6 rally in Washington that preceded the riot at the Capitol. In a field that may include one former governor and several other mainstream Republicans, said Ryan Horn, a Republican media strategist based in Omaha, “The problem is you get four or five people running and they all divide up the vote, and the chest-thumper has a floor of 20 or 25 percent, maybe, saying, ‘They’re all a bunch of pussy communists,’ and then Trump endorses him.” He said, “You’re going to get a really good case study of just how much can a Donald Trump endorsement standing alone in a Republican state do for somebody.”