McKinney defeated Tom Foley in Wilton and Fairfield County, but he lost most of the rest of the state to the Greenwich multimillionaire, who earned the Republican nod for governor in Tuesday's voting.
McKinney, the state senate's minority leader, picked up 230 votes compared with Foley's 219 in Wilton. A total of 11 percent of Wilton's 4,130 registered Republican voters turned out to cast ballots in Tuesday's primary.
McKinney hammered Foley in Fairfield County, taking 13,303 votes compared with Foley's 9,724. But Foley easily outdistanced McKinney in the state's other seven counties to win the primary.
Statewide, Foley outpolled McKinney 44,135 to 37,345.
Foley's next challenge is to defeat Democratic Gov. Dannel P. Malloy in November's general election.
In the race for lieutenant governor, Wilton Republicans cast 174 votes each for David Walker and the eventual winner Heather Somers. Penny Bacchiochi wound up with 98 votes.
It was a tight race for the position as Somers, the former Groton mayor, collected 34.5 percent of the more than 78,000 ballots cast statewide compared with Bacchiochi's 33.6 percent. Walker was a close third with 31.9 percent of the votes cast.
Wilton Republicans also came out strongly for comptroller candidate Sharon McLaughlin, handing her 288 votes compared with Angel Cadena's 106.
Statewide, McLaughlin crushed Cadena 53,277 to 17,187.
All vote totals are supplied by the secretary of the state's office.
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