The baseline congressional salary may be $174,000, but there are plenty of members of both the U.S. House and Senate who rake in far more each year.

Republicans dominate the list of Capitol Hill's wealthiest lawmakers, according to The Hill's recent ranking of the 50 richest members of Congress.  Thirty-one of the individuals on that list are members from the GOP, reports the publication, which reviewed 2011 financial disclosure forms to develop the rankings.

However, because lawmakers do not have to report exact figures for their assets and liabilities on those forms, instead proving those values in ranges, The Hill notes that some members of Congress may be far wealthier than its current lists indicates.

While Republicans may compose more than half of the list, seven of the top 10 richest lawmakers are all Senate Democrats.

Rep. Michael McCaul, R-Tex., is the wealthiest member of Congress, with a net worth of at least $290 million in 2011. McCaul's wealth stems from a variety of family trusts and connection -- for instance, his father-in-law is Lowry Mays, the founder of the radio broadcasting company Clear Channel Communications.

The senator from Massachusetts and one-time Democratic presidential nominee had a net worth of $198.8 million in 2011, much of that coming from wife Theresa Heinz Kerry's ties to the Heinz Ketchup fortune.

Kerry topped The Hill's list of wealthiest lawmakers in 2009 and 2010, before being surpassed by McCaul last year.

Rep. Darrell Issa, who made his fortune through the car security system company he founded Directed Electronics (OTCOTHER: DEIX), came in third with a net worth of $141 million.

Rep. Jared Polis saw his wealth skyrocket by $25 million in 2011, reaching a net worth of approximately $91 million.

The Democratic senator from Virginia, who was an early investor in Nextel, saw his wealth increase by $9 million last year to $85.9 million.

Sen. Jay Rockefeller is the great-grandson of American industrialist John D. Rockefeller, who became one of the richest men in history after founding Standard Oil.

Much of the current Rockefeller's wealth comes from his holding in trusts, valued at a minimum of $80 million.

The former Connecticut state attorney general saw his net worth rise to almost $78 million in 2011.

Lautenberg -- worth at least $57 million last year -- has consistently ranked among the richest lawmakers in Congress. The New Jersey senator co-founded the payroll services company Automatic Data Processing (NASDAQ: ADP), and reportedly still holds at least $1 million in stock in the firm.

Feinstein's wealth rose by almost $2 million in 2011 to reach about $47.4 million. Some of that cash is likely attributed to her husband, investment banker Richard Blum, who The Hill reports holds a large portfolio of stocks and investments.

The freshman congressman from Ohio, who founded the healthcare company LTC Management Services, was worth at least $36.7 million in 2011.