Overhauling the U.S. healthcare system, the most costly in the world, has been a high priority for President Barack Obama since he took office in January 2009.
Here is a timeline detailing the drive toward healthcare reform in the United States.
*1993: Democratic President Bill Clinton proposes a plan to create universal healthcare coverage for Americans relying largely on competition among private insurers, with government regulation to control costs. Clinton's fellow Democrats in Congress are divided, and solid opposition from Republicans and business interests kill it.
* November 4, 2008: Democrat Obama wins the presidency after making healthcare reform one of his campaign pledges. Key reform goals include: curbing rising healthcare costs, ending abusive practices by private insurers, and expanding insurance coverage to tens of millions of uninsured Americans.
* February 3, 2009: Former Senate Majority Leader Tom Daschle, pegged to spearhead Obama's healthcare reform quest, withdraws as the health and human services secretary nominee after revelations he was late paying income taxes. Kansas Governor Kathleen Sebelius, confirmed to the post after Daschle's demise, lacks Daschle's Capitol Hill savvy.
* March 5, 2009: Obama holds a White House forum to launch his reform effort, bringing together congressional, industry, union and think tank experts. Obama vows to have a plan passed by the end of 2009. The White House elects not to draft a detailed reform proposal, leaving the job to Congress.
* August 2009: Congress fails to meet Obama's deadline of passing initial healthcare legislation by August, as Republican and industry opposition hardens. Republicans oppose a proposal to create a new government-run health insurance program, called the "public option," to give Americans an alternative to private insurers. During August, people opposed to Obama's healthcare ideas confront Democratic lawmakers at "town hall" style meetings around the country, some denouncing the reform proposals as socialism.
* September 9, 2009: In an address to Congress, Obama asks for quick action on healthcare legislation. One Republican lawmaker shouts "you lie" when Obama says his plan would not pay for healthcare for illegal immigrants.
* November 7, 2009: The House of Representatives passes its version of healthcare reform legislation, including a public option, by a narrow 220-215 vote. In the end, 39 Democrats vote against the bill and only one Republican votes for it.
* December 24, 2009: The Senate passes its bill on a party-line 60-39 vote. Democratic leaders muster the 60 votes needed to block Republican procedural hurdles after negotiations with holdout Democrats including a deal with Nebraska's Ben Nelson exempting his state from expansion costs for the Medicaid insurance program for the poor. The bill has no public option.
* January 19, 2010: Republican Scott Brown wins a special Senate election in Massachusetts to replace veteran Democrat Edward Kennedy, who died of cancer in 2009. This deprives Democrats of the 60 votes needed to end the Senate procedural hurdle known as a filibuster. Democrats had been trying to merge the House and Senate bills into a single one that Congress would pass again and send to Obama to sign. After Brown's victory, Democrats set aside the efforts.
* February 22, 2010: Obama unveils his own healthcare proposal, drawn heavily from the Senate bill, three days before a bipartisan summit intended to rescue his reform effort.
* February 25, 2010: Obama presides over a bipartisan healthcare summit at Blair House, the presidential guest house across the street from the White House. The meeting is marked by tense exchanges between the president and Republican opponents of his healthcare plans, as the president .
* March 21, 2010: U.S. House of Representatives approves a sweeping overhaul of the $2.5 trillion U.S. healthcare system and sends along for Senate approval a package of changes made to the Senate bill.
(Writing by Will Dunham)