Dennis Clark Hollingsworth (born January 12, 1967) is an American politician who represented California's 36th State Senate district, which includes portions of San Diego and Riverside County, from 2002 to 2010.

Hollingsworth was affiliated with the conservative group ProtectMarriage.com and was instrumental in their unsuccessful legal battle to uphold the ban on same-sex marriage in California.

He was a business owner and Legislative Director for the Riverside County Farm Bureau prior to his election to the State Legislature.

In 2006, he authored a resolution to replace the statue of Thomas Starr King, a Unitarian minister who worked to keep California in the Union during the American Civil War, with one of Ronald Reagan in Statuary Hall.

[2] Shortly after midnight on the morning of February 18, 2009, after several days of late-night, contentious debates over closing a $42 billion gap in the state budget, Senate Republicans met in caucus where they voted to replace State Senate Republican Leader Dave Cogdill with Hollingsworth as minority leader.