Nebraska’s Republican Senate primary has long looked to be shaping up as a battle between Midland University president Ben Sasse and former state treasurer Shane Osborn. Throughout the campaign, Sasse has emphasized his determination to repeal Obamacare and fight the “Obamacare worldview,” while Osborn has emphasized his (controversial) military service and the fact that he’s not Sasse.  But as the Cornhusker State primary enters its stretch run (the primary is on May 13), a dark-horse candidate is making a move on the inside rail.

Sid Dinsdale, a highly successful banker who has avoided the attacks by Osborn that have simultaneously weakened both frontrunners (Sasse because he’s been the one attacked, Osborn because Nebraskans don’t like negative campaigns), has pulled within 3 points of Osborn and 9 points of Sasse in recent polling — after trailing each by at least 16 points in polling taken three months ago.  Dinsdale also recently picked up the endorsement of the Omaha World-Herald, which wrote, “Sensibly, [Dinsdale] would talk with those on the other side of the partisan aisle, and he has the tools to be persuasive in such conversations.”