What is the source of this estimate ?
In 2008, the last primary both parties did not have an incumbent, the Republican total vote was 234,851 and the Democrat total vote was 284,090.
In 2012 the Republican primary vote total 248,475.
Tonight, if the percentages in are correct, and don't exceed the estimate, the Republican total would be 263,314 and the Democrat total 240,912. Perhaps the Independents are moving around and Trump brought in some new voters.
Perhaps the Independents moved in and brought Kashich some votes.