The next step in the health care debate centers on a procedural move known as reconciliation.

The budget reconciliation process would allow Democrats to avoid a filibuster of legislation to amend a health care bill — a necessity since the Jan. 19 election of Scott P. Brown (R-Mass.) knocked the Senate Democratic majority down to 59 senators.

Sixty votes, or a three-fifths majority, are needed in the Senate to limit debate and end a filibuster.

In addition, only a simple majority is needed to pass a bill under reconciliation process, which means Democrats need 50 votes with Vice President Joe Biden as the tie-breaker. Debate on a reconciliation measure is limited to 20 hours in the Senate.

Reconciliation was created in 1974 (PL 93-344) as a method for changing existing laws to bring federal spending in line with the annual budget resolution. Since then, several major pieces of legislation have been enacted under the reconciliation process.

Democrats likely will use reconciliation on a smaller, "side-car" bill that would make fixes to the broad health care overhaul legislation. The reconciliation bill would be modeled on Obama's health care proposal released in February.

Under this strategy, the Senate would promise to pass the side-car bill under the reconciliation process in exchange for the House clearing the health care bill (HR 3590 ) that the Senate passed in December.

The Democrats' finish line: President Obama signing both the health care bill and the reconciliation legislation that would modify that bill into law.

Yet even under the expedited reconciliation process, moving the health care changes bill won't be easy.

Senators can raise points of order against provisions of the reconciliation bill under the Byrd Rule. The Senate adopted the rule, written by Sen. Robert C. Byrd (D-W.Va.) in 1985 as a way to discourage extraneous provisions in reconciliation bills.

A senator opposed to a part of the reconciliation bill can raise a point of order against it under the Byrd Rule. The chair, aided by the Senate parliamentarian, then determines whether the challenge will be upheld.

If it is, supporters are forced to get a three-fifths majority, or 60 votes, to waive the point of order made under the Byrd Rule and allow the challenged provision to stay in the bill.

It is unclear what provisions Republicans might target under the Byrd Rule, but several challenges are expected.

Republicans oppose the use of reconciliation on any health care legislation, saying the process was not intended for use on large and complex bills. 

"The use of expedited reconciliation process to push through more dramatic changes to a health care bill of such size, scope and magnitude is unprecedented," Sen. Orrin G. Hatch (R-Utah) wrote in a Feb. 22 letter to Obama.

However, both parties have used reconciliation to pass large pieces of legislation, including several related to health care. Since reconciliation was created, 11 of the 19 enacted reconciliation bills have included major health care provisions.

For example, Congress used reconciliation in 1997 to create the Children's Health Insurance Program, which provides medical insurance to uninsured children. The bill (PL 105-33) also reduced Medicare reimbursements to health care providers and increased individual premiums for physician coverage.

Reconciliation was also used in 1986 (PL 99-272) to establish COBRA health insurance benefits, which allows workers who are laid off to keep employer-provided insurance at the company rate.

Lately, reconciliation has meant major Senate floor battles. When Republicans used reconciliation in 2006, then-Vice President Dick Cheney had to come in and break a tie in the divided Senate. The bill (PL 109-171), which reduced Medicaid reimbursement rates for prescription drugs and allowed states to reduce some Medicaid benefits, passed 51-50.

In 2007, the last time reconciliation was used, floor debate devolved into intense bickering – to the point where frustrated Majority Leader Harry Reid (D-Nev.) threatened to try to change Senate rules on offering amendments. Unrelated amendments blocked progress on a bill to increase student aid (PL 110-84) during a voting session that lasted until nearly 1 a.m.

Partisan rancor grew as Democrats offered an amendment asking then-President Bush not to pardon I. Lewis "Scooter" Libby, a former chief of staff to then-Vice President Cheney who was convicted of perjury and obstruction of justice.

For their part, Republicans had an amendment criticizing former President Bill Clinton for "granting clemency to terrorists." Finally, the bill passed 78-18.

The bitter tone of debate on health care indicates that senators might be into a similar rough ride if reconciliation is used this year.

Emily Ethridge writes for Congressional Quarterly.

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