There will be one less primary election in Connecticut on Aug. 12.

Matthew Brennan has decided not challenge fellow Winsted resident Michael J. Renzullo, the endorsed Democratic candidate in the 30th state Senatorial District race, Secretary of the State Susan Bysiewicz's office said Wednesday.

Renzullo will now face the Republican incumbent, Sen. Andrew Roraback of Goshen, in the November election.

There are currently 21 primaries scheduled. They include a battle in the 4th Congressional District race between endorsed Democrat Jim Himes and Lee Whitnum, who collected enough signatures to force the primary.

The remaining 20 primaries are for state legislative races -- four in the Senate and 16 in the House of Representatives.

Some of the matchups are happening in districts where an incumbent is not seeking re-election. For example, in the 9th House District, held since 1999 by Rep. Christopher Stone, D-East Hartford, there are two primaries.

Three Republicans from Manchester -- Michael W. Crockett, Dennis A. Brenner and Clifton E. Thompson, the party-endorsed candidate -- are vying for the GOP spot on the November ballot. On the Democratic side, endorsed candidate Jason Rojas of East Hartford is facing a primary challenge from Joseph S. Hachey of Manchester.

A number of incumbents, however, are facing challenges from fellow party members, including Sen. John W. Fonfara, D-Hartford, Rep. Marie Lopez Kirkley-Bey, D-Hartford, Rep. Selim G. Noujaim, R-Waterbury, Rep. Corky Mazurek, D-Wolcott, Rep. Deborah Heinrich, D-Madison, Rep. Terry Backer, D-Stratford, Rep. Christopher Caruso, D-Bridgeport, Rep. Andres Ayala Jr., D-Bridgeport, and Rep. Robert T. Keeley, D-Bridgeport.