HARTFORD -- Republicans outperformed Democrats last week in primary-election turnout by 8.5 percentage points.

Secretary of the State Denise Merrill said Thursday that Democrats showed up at slightly lower rates than usual, while slightly more than an average number of Republicans voted.

Attendance for both parties was highest in the 5th Congressional District, fueled by high-profile congressional primaries won by state Sen. Andrew W. Roraback, R-Goshen, and Democrat Elizabeth Esty, of Cheshire.

Turnout was also pumped up by 5th District U.S. Rep. Chris Murphy's primary battle with Susan Bysiewicz, the former secretary of the state, for the Democratic nomination for U.S. Senate.

The Democrats' 19.2 percent turnout was the lowest since the September 1998 primary attracted 18.7 percent. The Republicans' 27.7 percent was slightly higher than most primaries dating back to 1986, but they failed to meet the August 2010 level of nearly 29.8 percent.

In the 5th District, the total turnout of 27.2 percent last week included 23.5 percent of Democrats and 32.3 percent of Republicans. Roraback's hometown of Goshen had the highest Republican turnout in the state, with 59.4 percent of registered GOP voters casting ballots. The Democrats' highest turnout was 52.1 percent in Cornwall.

In the 4th Congressional District of southwestern Connecticut, Democrats voted at a 17.4 percent rate, while 26.9 percent of Republicans cast ballots.

Overall, 113,538 registered Republicans voted out of 409,723 party members statewide. The turnout of 138,004 registered Democrats was from among the 717,241 party members.

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