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When President Obama first began his push for health care reform a year ago, he was full of optimism and brimming with bipartisan brio.

Now, after a year of several blown self-imposed deadlines, unexpected setbacks and incremental victories, the president is taking his final stand to get a health care bill passed -- a push likely to last for the next few weeks.

A senior White official described the latest push to Fox News as a one-shot deal -- and if it doesn't work, it doesn't work. Obama underscored that he's stepping up his efforts with an eye to the finish line.

"I will do everything in my power to make the case for reform," he said Wednesday.

But Republicans remain united in their opposition despite Obama's bipartisan overtures.

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"It's not too late: We can, and we must, stop this government takeover of health care," said Rep. Parker Griffith, a retired physician and a first-term congressman from Alabama who switched parties in December and delivered the Republican message Saturday.

Griffith said leaders of the Democratic Party he left last year were missing the point.
"For them, health care reform has become less about the best reforms and more about what best fits their 'Washington knows best' mentality -- less about helping patients and more about scoring political points," he said. "This is no idle observation. I've witnessed it firsthand."

It's been a challenging year, and Obama never thought he'd spend this much of his presidency trying to get health care legislation passed.

The president kicked off his push for reform a year ago with a huge health care summit, complete with break-out sessions for lawmakers and health care experts. Afterward, he quoted Rhode Island Democrat Sheldon Whitehouse.

"This isn't a 'Harry and Louise' moment. It's a 'Thelma and Louise' moment," he said with laughter. "We're in the car headed toward the cliff and we must act."

Harry and Louise was a reference to ads that helped doom Bill Clinton's health care reform efforts in the 1990s. Obama scored an early victory when the same actors backed his plan for health care reform.

Obama reminded his audience a year ago about what happened in Thelma and Louise.

"If you actually saw the movie, they did drive over the cliff," he said, laughing. "So I just want to be clear that's not our intention here."

Perhaps the president laughed too soon. On May 11, he told business leaders health care would be done in months.

On June 11, Obama took health care on the road for the first time to Green Bay.

Then came the summer of health care discontent. Town halls turned into cauldrons of rage. Days later, the president denounced what he called willful misrepresentations and outright distortions spread by the very folks who would benefit the most by keeping things exactly as they are.

But that didn't turn things around, so Obama convened a joint session of Congress. A month later, still no action. So doctors, outfitted in lab coats, came to Obama' side.

A month later, the House passed its version of reform. On Christmas Eve, a day after the president was to start his Hawaiian vacation, the Senate passed its bill – one laded with special deals for Democrats from Louisiana, Nebraska, Florida and Connecticut.

"I look forward to working with members of Congress in both chambers over the coming weeks," he said at the time."

But weeks turned into months as Democrats struggled to bridge their differences over the two bills. Then Democrats surprisingly lost their supermajority in January when Republican Scott Brown captured the Massachusetts Senate seat previously held by Ted Kennedy. That prompted Democrats to consider using reconciliation, a rare tactic that allows a simple majority to pass legislation and prevent the minority party from talking a bill to death.

Obama held one last bipartisan health care summit last week where he threatened to use reconciliation if Republicans don't jump onboard.

"And then that's what elections are for," he said at the end of the seven-hour summit.

On Wednesday, with more doctors in white coats, Obama said he was giving it one last try.

"At stake right now is not just our ability to solve this problem, but our ability to solve any problem," he said.

Fox News' Major Garrett contributed to this report.