Sponsorship and Cosponsorship of Senate Bills

Sponsorship and Cosponsorship of
Senate Bills

Updated February 5, 2021
Congressional Research Service

Sponsorship and Cosponsorship of Senate Bills

Senator who introduces a bil or resolution in the Senate is cal ed its sponsor. Several
Senators together may introduce a measure, but only the Senator whose name appears
first on the bil is considered its sponsor; the others are cosponsors. A bil can have only
A one sponsor, but there is no limit on the number of cosponsors it may have.1
Sponsorship of a Bill
At the beginning of each new Congress, the Senate traditional y adopts a standing order al owing
Senators to introduce bil s and resolutions at any time the chamber is in session by presenting
them to the bil clerk seated at the desk on the Senate floor.2 Most measures are introduced in this
fashion. Senators may also introduce measures from the floor as part of “morning business” under
Rule VII. In practice, however, morning business seldom occurs as provided in Rule VII. Instead,
on most days, the Senate arranges by unanimous consent for a period of morning business to
occur at some later point. Senators may introduce measures from the floor during this period.3
Senators typical y sponsor bil s they support. A Senator may introduce a bil as a courtesy, such as
legislation proposed by the President, in which case the bil would be designated in the
Congressional Record as having been introduced “by request.” A Senator may also introduce
legislation on behalf of another Senator without having to assume sponsorship themselves.4 Once
a bil has been handed to the clerk, it becomes the property of the Senate and cannot be
withdrawn. A bil sponsored by a Senator who has since departed the chamber can stil be acted
upon by the Senate. The text of a departed Senator’s bil also may be introduced as a new bil
with a sitting Senator identified as its sponsor.
Some bil s become popularly associated with the names of two or more Senators; for instance, the
Gramm-Rudman-Hollings Deficit Control Act of 1985, the Kennedy-Kassebaum Health
Insurance Act of 1995, or the McCain-Feingold Campaign Reform Act of 2002. Although these
popular associations may suggest otherwise, Senate rules do not al ow a bil to have multiple
sponsors. Even stil , the strategy of associating legislation with the names of two or more
Senators can be useful in gaining support across partisan or ideological ranks. As Senator Ted
Kennedy (D-MA) explained: “When Strom [Thurmond] and I introduce a bil together, it is either
an idea whose time has come, or one of us has not read the bil .”5 A “Kennedy-Thurmond” bil
would have conveyed a clear signal that the measure enjoyed support from across the ideological
Most measures are introduced by individual Senators, but Senate committees may also report an
“original” bil for chamber consideration. As Senate Rule XXV states, standing committees have
“leave to report by bil or otherwise on matters within their respective jurisdictions.” The relevant
committee chair is general y considered the sponsor in these instances, although the measure is

1 Congressional Record, vol. 50, part 6, (October 27, 1913), p. 5798.
2 Congressional Record, daily edition, vol. 167 (January 3, 2021), p. S8.
3 For further information on bill introduction, see CRS Report R44195, Introducing a Senate Bill or Resolution, by
Mark J. Oleszek.
4 In these cases, the bill will appear in the Congressional Record as having been introduced by one Senator for another
Senator. For instance, on January 4, 2017, Minority Leader Charles Schumer introduced S. 30 on behalf of Senator
Feinstein, who sponsored the bill. See Congressional Record, daily edition, vol. 163 (January 4, 2017), p. S59.
5 Quoted in Walter Oleszek, Roger Davidson, Eric Schickler, and Frances Lee, Congress and Its Members, 16th ed.
(Washington, DC: CQ Press, 2017), p. 221.
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Sponsorship and Cosponsorship of Senate Bills

perhaps best understood as a product that incorporates views and input from other committee
members as wel .6 Original bil s may not have cosponsors.
Cosponsorship of a Bill
When Senators introduce bil s, they commonly attach a form listing the names of cosponsors.7
Cosponsorship is general y understood to signify a Senator’s support for the proposal. Prior to
introduction, Senators may cosponsor a measure by contacting the office of the sponsor and
requesting that their names be included on the bil or resolution. Initial (or “original”) cosponsors
can be added until the measure is presented to the bil clerk on the floor of the Senate chamber.
Thereafter, unanimous consent is required to include additional cosponsors on the measure.8 A
Senator may offer this request when recognized on the Senate floor, or, alternatively, deliver to
the cloakroom a cosponsorship form that bears an original signature of the Senator requesting to
be added as a cosponsor.
The names of additional cosponsors wil appear on the printed version of the bil only if there is a
subsequent printing of it. Under regulations set forth by the Joint Committee on Printing, a bil
cannot be reprinted solely for the purpose of adding cosponsors (even by unanimous consent).9 A
current list of cosponsors may be identified through a search of Congress.gov, an online database
of legislative activity, or the Congressional Record.10
Supporters of a bil often seek cosponsors to demonstrate its level of support among Senators.
One of the most common techniques to attract cosponsors is the “Dear Colleague” letter, a notice
delivered to some or al Senate offices either in print or by email soliciting support for the bil .
These letters typical y explain the issue or problem the legislation seeks to address, the key policy
elements it contains, and the likely impact it would have if passed into law. Contact information
of a staff aide is usual y included for the benefit of Senate offices interested in cosponsoring the
measure. No Senate rules or any formal procedures govern “Dear Colleague” letters. They are, in
effect, advertisements for the sponsoring Senator’s legislation.11

6 T echnically speaking, an original bill is not considered to have a sponsor under Senate rules. When an original bill is
reported and a final draft is printed, a Senator (usually the chair) will deliver the final draft to the bill clerk’s desk on
the chamber floor where it will be assigned a bill number and placed on the calendar. T he name of the Senator who
brought the legislation forward will be indicated on the bill, but this indication is not tantamount to sponsorship. For
instance, the Senate Committee on Armed Services reported an original bill (S. 1519) in July 2017 authorizing
appropriations for the U.S. military and the Department of Defense. T he text of S. 1519 was drafted, marked up, and
reported by the committee. Because it was the chair of the Armed Services Committee who presented the legislation to
the bill clerk, the bill indicated, “Mr. McCain, from the Committee on Armed Services, reported the following original
bill.” Under Senate rules, however, Senator McCain did not sponsor the bill.
7 Cosponsorship forms are available for download in portable document format (PDF) at http://webster.senate.gov. This
form may be used either to add or subtract cosponsors of bills, resolutions, and amendments.
8 After a bill has been introduced it requires unanimous consent to remove a Senator as a cosponsor, and either the
sponsor or a cosponsor may make this request. Proceedings to this effect can be found in the Congressional Record,
vol. 153, part 1 (May 2, 2007), p. S5493.
9 Congressional Record, vol. 97, part 2 (March 21, 1951), p. 2723.
10 Available at http://congress.gov. Cosponsors who are added to a bill after its introduction will appear in the
Congressional Record under the heading “ Additional Cosponsors.”
11 For further information, see CRS Report R44768, “Dear Colleague” Letters in the House of Representatives: Past
Practices and Issues for Congress
, by Jacob R. Straus.
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Sponsorship and Cosponsorship of Senate Bills

On the day a measure is introduced, the sponsor may direct the clerk to hold the bil at the desk
for the purpose of collecting cosponsors prior to its referral to committee. To hold a bil at the
desk beyond the date of its introduction requires the unanimous consent of the Senate.12
The connection between cosponsorship and legislative outcomes has been the subject of
considerable scholarly research. Much of the empirical work in this area suggests that
cosponsorship has a positive but limited impact on a bil ’s prospects for final passage. As one
prominent study concluded:
[C]osponsorship matters for legislative success, but only barely. Significant effects due to
cosponsorship crop up at different stages of the legislative process. When bills are
referenced to a committee, bills with cosponsors are more likely than bills with no
cosponsors to receive some consideration. Likewise, cosponsored bills are more likely to
make it out of committee, however, the impact of cosponsorship is slight. It has even less
impact on the final passage of bills.13
Decisions to cosponsor legislation can be made for a variety of reasons, some of which might be
unrelated to the text of the bil itself. As such, cosponsoring a bil should not be equated with a
vote for final passage. In some cases the text of a measure might have been amended following its
introduction in ways a cosponsor can no longer support. In addition, Senate norms of behavior
have long emphasized collegiality and deference to one’s colleagues, and some Senators may
view cosponsorship as the legislative equivalent of a common courtesy. Senator Everett Dirksen
(R-IL) expressed the sentiment this way:
The bill may be 50 pages long, and I will not know what is in it from the enacting clause
to the last period. But I do not wish to affront a Senator, and if he gives me a sufficient
sales talk, I am likely to say, “All right, go ahead and add my name.” Then, when we finaly
get around to it, I discover at long last what I actually put my name to. Perhaps I will not
like it. But how do you get out from under it? Because my name is there, notwithstanding.
I could at some point take it off, but one does not wish to affront a fellow Senator by doing

Author Information

Mark J. Oleszek

Analyst on Congress and the Legislative Process

This report was originally prepared by former CRS Specialist Richard C. Sachs.

12 During the 90th Congress (1967-1968) the Senate debated at some length the practice of holding a bill at the desk to
gain cosponsors. See Congressional Record, vol. 113, part 3 (February 16, 1967), pp. 3725-3734.
13 Rick Wilson and Cheryl Young, “Cosponsorship in the U.S. Congress,” Legislative Studies Quarterly, vol. 22, no. 1
(February 1997), p. 40.
14 Congressional Record, vol. 113, part 3 (February 16, 1967), p. 3725.
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Sponsorship and Cosponsorship of Senate Bills

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98-279 · VERSION 17 · UPDATED