WASHINGTON - President Barack Obama said on Wednesday it is time to pass his sweeping healthcare overhaul using only a slim Democratic majority in Congress if necessary, saying the issue is too important to be delayed by politics after a year of debate.

The American people are waiting for the administration to lead, Obama said, flanked by white-coated doctors and nurses in the White House East Room.

Everything there is to say about health care has been said and just about everyone has said it, Obama said. So now is the time to make a decision about how to finally reform health care so that it works, not just for the insurance companies, but for America's families and businesses.

Obama said his plan included ideas from both his fellow Democrats and rival Republicans, who staunchly oppose the idea of a sweeping overhaul of the $2.5 trillion healthcare industry that accounts for one-sixth of the U.S. economy.

Obama said he opposed the Republican call to throw out broad bills passed by the House of Representatives and Senate last year and begin again with a more step-by-step approach.

Given these honest and substantial differences between the parties about the need to regulate the insurance industry and the need to help millions of middle-class families get insurance, I do not see how another year of negotiations would help, Obama said.

Insurance companies are continuing to raise premiums, he said. For us to start over now could simply lead to delay that could last for another decade or even more, Obama said.

Wall Street shrugged off the speech. The Morgan Stanley Healthcare Payor index of health insurer stocks was up more than 1 percent on Wednesday.

Democrats have been preparing to pass a final measure in the Senate without opposition support through a process called reconciliation, which requires only simple majority approval instead of the usual 60 votes needed in the 100-member chamber.

Obama did not use the word reconciliation, a term not understood by many Americans, but made clear he supported that process with his comments urging Congress to vote.

No matter which approach you favor, I believe the United States Congress owes the American people a final vote on health care reform, he said.

The political stakes are enormous. Obama's approval ratings have dropped during the healthcare fight in the face of unified Republican opposition and public worries about an unemployment rate hovering around 10 percent.

With more than one third of the Senate and all seats in the House up for grabs in November elections, his fellow Democrats want to move past healthcare to focus on job creation and the economy.

Republicans contend the public does not want a massive plan, which they say is too expensive for a government running huge budget deficits.

Americans don't want us to tack a few good ideas onto a bill that reshapes one-sixth of the economy, vastly expands the role of government and which raises taxes and cuts Medicare to pay for it all, Senate Republican leader Mitch McConnell said.

Using reconciliation to pass the final healthcare bill would be a two-step process. The House would approve the Senate-passed bill and changes to the Senate bill sought by the House would be passed separately through reconciliation.

(Additional reporting by Steve Holland; editing by Vicki Allen)