You got me that time...
Before we get too excited, Burns likely needs a cushion of I don't know how many votes, because Yellowstone County - according to ABC/Associated Press, yet to be counted - has gone to Tester.
But my source for this is not solid; it's a post in NRO's Corner Blog: http://corner.nationalreview.com/post/?q=MzFhMjhlNDNlNWRkMWY4NWExOWM2MjgxZjBiODdjYmE=