In what had been a surprisingly close race that had given Republicans a scare, incumbent GOP Sen. Pat Roberts has won his re-election bid over Democrat-turned-Independent Greg Orman. You might not call it an upset, but Orman had been leading in nearly every poll ever since it had become a two-person race.
Democrats forced out the official Democratic candidate in August, leaving it as a fight between Roberts and Orman. Ever since then, Roberts' campaign had worked hard to paint Orman as the Democrat that he had been in the past - funded by liberal billionaires, owner of liberal positions, and aided by Democratic campaign operatives.
It worked. We might have to look at the exit polling, but Roberts had been losing among independents, and only winning 80% or so of registered Republicans. A win means that the biggest threat to a GOP loss of a seat is over with.