Eye surgeon Rand Paul cruised to the Republican Senate nomination on Tuesday, defeating Secretary of State Trey Grayson in an outcome that closely reflected public polling in the contest.

With just 37 percent of precincts reporting, the Associated Press called the contest for Paul, who had 59 percent to Grayson’s 37 percent.

Paul’s victory is certain to be viewed as a major victory for the tea party movement, which had championed Paul in the contest. What’s less clear is determining how much Grayson’s loss is a rejection of the Kentucky GOP establishment — which was clearly in the secretary of state’s corner. Grayson had the backing of Senate Minority Leader Mitch McConnell, who is considered the godfather of the state’s modern Republican Party. But recent polling indicated that while GOP voters preferred Paul, they also still have high opinions of McConnell.

In the Democratic Senate race, Attorney General Jack Conway held a strong lead over Lt. Gov. Daniel Mongiardo with just under 38 percent reporting. Conway, who had 51 percent compared to 37 percent for Mongiardo, appeared to benefit from strong early returns from his base in Louisville.