The U.S. Congress is made up of two chambers, the Senate and the House of Representatives. Each state is allotted two Senators while the number of representatives each state has is determined according to population. There are 435 seats and with the onset of the 10-year census, redistribution of those seats take place so that a state may gain or lose the number of representatives it had for the previous 10 years. The Senate and the House each have their own particular official and unofficial requirements for election.

Age

The U.S. Constitution lays out the age qualifications for being elected to the House of Representatives and the Senate. To be elected as a member of the House of Representatives, a person must be at least 25 years old. To be elected to the Senate, a candidate must be at least 30 years old.

Citizenship

The U.S. Constitution always lays out requirements for U.S. citizenship. To get elected as a member of the House of Representatives, the candidate must have been a United States citizen for the previous seven years. To get elected to the U.S. Senate the candidate must have been a U.S. citizen for the previous nine years.

Residency

For election to both the House and Senate, the candidate must be a resident of the state he is representing. Things get a little strange for members of the House of Representatives, however. While a member of Congress must be a resident of the entire state he is representing, he does not actually have to live in the district that elected him.

Incumbency

While not an official requirement, history has proved that it is far easier to maintain a seat in Congress than to beat an incumbent. Except for those rare elections where a sweeping change takes place, the average election witnesses 90 percent of all incumbents being voted back into office. The rate of incumbency is usually even higher for members of the House.

Race

Race is also not an official requirement, but historically speaking white candidates have a far greater chance of being elected than minority candidates. The most racially diverse Congress in U.S. history was the 109th Congress and out of the 535 members 70 were of a minority race.

Gender

Another unofficial requirement to get elected to Congress is to be male. There is no law against women being elected, obviously, but the 109th Congress again is the most diverse Congress in terms of gender. The number of women in that Congress, though still minute compared to the number of men, is positively gargantuan in comparison to the gender gap that has traditionally existed. The 109th Congress featured 68 women out of 535 in the Senate and House combined.

Money

It may not be written into the Constitution, but with each passing year it becomes clearer that one of the unwritten requirements of getting elected is to have money. The median net worth of a member of Congress was estimated at $675,000 and the median net worth of a Senator was estimated at $1.7 million in 2008. With the average cost of a congressional campaign over $1 million and the average cost of a Senate triple that just in smaller states, there is little doubt left that a major requirement for becoming a lawmaker in Washington is to be rich.