Congressional members' personal wealth collectively rose by more than 16 percent between 2008 and 2009, despite the economy-busting effects of the Great Recession, according to a new study released Wednesday by the Center for Responsive Politics.

The study -- based on federal financial disclosure data -- also showed that more than half of all members were millionaires.

Rep. Darrell Issa (R-Calif.) topped the list with holdings of about $303.5 million, a 21 percent gain from his worth the year before, the report said. Following Issa were Rep. Jane Harman (D-Calif.) -- worth $293.4 million -- and 2004 Democratic presidential candidate Sen. John Kerry (D-Mass.) -- worth $238.8 million. Harman and Kerry realized wealth gains of 19.8 percent and 14.3 percent, respectively.

Issa made his fortune, in part, as founder of Directed Electronics Inc., a California-based electronics company that makes products ranging from car alarms to home theater systems. The company's flagship product, the "Viper" car alarm, which elicits siren that is said to be a recording of Issa's voice saying, "please step away from the car."

Sen. Mark Warner (D-Va.), Rep. Jared Polis (D-Colo.), Sen. Herb Kohl (D-Wis.), Rep. Vernon Buchanan (R-Fla.) and Rep. Michael McCaul (R-Texas) rounded out the list of lawmakers who, in 2009, were worth more than $100 million.

For all members of Congress -- regardless of chamber -- median wealth in 2009 reached $911,510, up from $785,515 in 2008. From 2007 to 2008 overall congressional wealth slipped by more than five percent.

Members of the Senate were considerable wealthier than those in the House. In 2009, the median wealth of a House member stood at $765,010, while a US senator was worth, on average, about $2.38 million.

The Center for Responsive Politics (CRP), which published the study, is a nonpartisan research group based in Washington that tracks money and the effect of money in politics.

“Few federal lawmakers must grapple with the financial ills -- unemployment, loss of housing, wiped out savings -- that have befallen millions of Americans,” said Sheila Krumholz, the Center for Responsive Politics’ executive director. 

Congressional representatives on balance rank among the wealthiest of wealthy Americans and boast financial portfolios that are all but unattainable for most of their constituents.”