The following are graphs showing the frequency distribution of bill cosponsorship in the United States House of Representatives and United States Senate as of February 13, 2009. Cosponsorship is the signing of a member of Congress’ name to a bill, an act that formally indicates support for the bill. The x-axis in each graph represents the number of cosponsors for a bill, and the y-axis represents the number of bills with that number of cosponsors.

Every bill must have a principal sponsor, but not every bill has a cosponsor. Indeed, the modal category in the House of Representatives so far is that of bills without any cosponsors. At this admittedly early point in the 111th Congress, 417 bills in the House have no cosponsors, and an additional 132 bills have just one cosponsor. The frequency distribution drops off pretty quickly from there, with only a handful of bills gaining more than a hundred cosponsors. Three bills have more than 190 sponsors, the clear outliers in the House distribution. The following are the top five bills in terms of cosponsorship in the House of Representatives:

1. H.R. 707, to provide mail vouchers to members of the armed forces serving overseas. Sponsored by Representative Kathy Castor. 196 cosponsors reported as of 2/13/09, 49 Republicans and 149 Democrats.

2. H.R. 12, a measure by Representative Rosa DeLauro that was added to the Lilly Ledbetter Fair Pay Act of 2009. 193 cosponsors reported as of 2/13/09, 0 Republicans and 193 Democrats.

3. H.R. 11, the Lilly Ledbetter Fair Pay Act of 2009. Sponsored by Representative George Miller, this bill was passed by the House and Senate and signed into law by President Barack Obama. It removes the requirement that a person find out about pay discrimination within 6 months of its inception in order to seek relief from it. Cosponsored by 190 members of the House, all of them Democrats.

4. H.R. 226, to prevent the FCC from reintroducing a Fairness Doctrine that broadcasters using the public airwaves leave equal time for dissenting views. Sponsored by Representative Mike Pence and cosponsored by 174 members of the House: 170 Republicans and 4 Democrats.

5. H.R. 235, sponsored by Representative Howard Berman, this bill would “repeal the Government pension offset and windfall elimination provisions.” 159 cosponsors, 56 of them Republicans and 103 of them Democrats.

On the Senate side of things as of February 13, 168 bills have no cosponsors, and an additional 84 bills have just one cosponsor. The frequency distribution drops off pretty quickly from there, with only a handful of bills gaining more than a hundred cosponsors. One bill is an outlier with 52 cosponsors, which may not sound like much compared to numbers in the House of Representatives, but then again the Senate has fewer than 100 functioning members at the moment. The following are the top five bills in terms of cosponsorship in the United States Senate:

1. S. 181, the Senate version of the Lilly Ledbetter Fair Pay Act of 2009. With principal sponsorship of Senator Barbara Mikulski, this bill when passed into law removed the requirement that a person find out about pay discrimination within 6 months of its inception in order to seek relief from it. Cosponsored by 52 members of the Senate (not including now Secretary of State Hillary Clinton), 50 of them Republicans, 2 of them Independents (Bernard Sanders and Joseph Lieberman) and 1 Republican (Olympia Snowe of Maine).

2. S. 34, the Senate version of the bill to prevent the Federal Communications Commission from reintroducing the Fairness Doctrine that broadcasters using public airwaves lend equal time for opposing viewpoints. Introduced in the Senate by Senator Jim DeMint, the bill had 29 cosponsors on February 13, all of them Republicans.

3. S. 211, introduced by Senator Hillary Clinton before she departed to become Secretary of State, would create a nationwide 2-1-1 phone number that would connect to a local community center with information on social services and volunteer opportunities. The bill had 26 cosponsors as of February 13, 6 of them Republicans, 19 of them Democrats, and 1 of them the Independent Joseph Lieberman.

4. S. 388, a bill to extend the numerical cap for foreign agricultural workers returning to the United States after being here on temporary H-2B status. Sponsored by Senator Barbara Mikulski, the bill has 24 cosponsors, 13 of them Republicans, 10 of them Democrats and 1 of them the Independent Joseph Lieberman.

5. S. 231, introduced by Senator Joseph Lieberman, would set aside part of the Alaska National Wildlife Refuge with wilderness protection. As of 2/13/09, cosponsored by 24 Democrats and the Independent Bernie Sanders.

Look for updated reports on cosponsorship in the U.S. Congress to come regularly to you throughout the course of the 111th Congress.