I see more turbulence and undercurrents among Republican primary voters than usual. The evidence is that incumbents -- both those the mainstream media call tea partyers and those they call the party establishment -- have been prevailing by tenuous margins in primaries that in the pre-tea party years would almost certainly not have been seriously contested.
Take Kansas. There Sen. Pat Roberts was renominated over challenger Dr. Milton Wolf by just a 48 percent to 40 percent margin -- a victory, but an embarrassingly low margin for someone who has been in Congress for 34 years.
Wolf, a second cousin of President Obama, made much of the fact that Roberts maintains only a nominal residence in the state. But the doctor was hurt when it was revealed that he circulated X-rays of wounded patients with macabre comments.
Roberts, perhaps awakened by the near-defeat of fellow septuagenarian and longtime incumbent Thad Cochran in Mississippi, worked hard in affluent Johnson County, just outside Kansas City, which casts one-fifth of the primary vote. He held Wolf to a 107-vote margin there and carried 92 of the other 104 counties.
Also renominated was Gov. Sam Brownback, by 63 percent to 37 percent. Brownback's push for tax cuts has been controversial; critics charge it hasn't stimulated growth and has forced the state to cut needed spending. Some 100 current and past Republicans officials signed a letter supporting his Democratic opponent.
This is the latest chapter in a long-simmering intra-party fight between conservatives and moderates. Brownback prevailed, but by a margin that suggests problems in November.
Kansas also saw serious challenges of incumbents in two of its four congressional districts. In the 1st District, Tim Huelskamp, a frequent rebel against the House Republican leadership, won, but by only 54 percent to 46 percent.
There was a clearer verdict in the Wichita-centered 4th District, where incumbent Mike Pompeo led his predecessor, Tom Tiahrt, by 63 percent to 37 percent.
Tiahrt ran as a champion of earmarks, arguing they were necessary to help Wichita's troubled private plane industry. Pompeo pledged no earmarks, and various conservative groups supported each candidate.