Wong/GettyNancy Pelosi gets a big hand from House members after signing the Senate health care reform bill on Monday.

WASHINGTON - Those who know Nancy Pelosi best say without her, President Obama wouldn't have been able to pop open the champagne bottle over his momentous health care win.

Pelosi loves quoting legendary House Speaker Tip O'Neill, and her fans say she's now in the same league as the Democratic lion of the House.

"This has been a remarkable string of victories. Sometimes you look down the field and say, 'How is she going to pull this one off?' And the next thing you know she scores," said Rep. Anthony Weiner (D-Brooklyn).

"The real story here is how Nancy Pelosi dragged Harry Reid and Barack Obama over the finish line," he added.

Asked in an ABC interview Monday if she's the "most powerful woman in 100 years," Pelosi paused, then smiled, "That sounds good."

Even fervent Obama boosters concede Pelosi's clear-eyed commitment to liberal reform, steely determination and tenacity in whipping nervous Democrats into line made the difference between ignominious failure and victory.

"She's Lyndon Johnson in a skirt," Democratic political strategist Mark Siegel said of the San Francisco grandmother, who turns 70 Friday. "She was patient, tireless, persistent and cajoling - and she pulled off what no one else could."

Rep. Joe Crowley (D-Queens) thinks her work ethic and strategic vision top all her attributes. "I can't think of a smarter person on policy or politics," he said. "And I've never seen anyone work as hard at it as she does at both."

Long before Obama gave Rep. Dennis Kucinich (D-Ohio) a ride on Air Force One, Pelosi made a strong gesture for his vote by allowing three hours of debate on a resolution to end the war in Afghanistan.

She also waited out pro-life colleague Bart Stupak of Michigan, knowing he had gone too far out on a limb and would cave and ultimately vote yes.

"She said, 'We're not negotiating,' and she let him hang out there alone for a while. She knew he would come around," said a leadership source.

If she feels burned or insulted, beware. Rep. Steve Lynch (D-Mass.) recently made a dismissive comment that angered Pelosi, whose dad was a machine-pol mayor of Baltimore.

"The speaker doesn't tolerate nonsense," said a lawmaker familiar with the exchange. "I wouldn't want to be Steve Lynch right now."

Since becoming the first woman speaker four years ago, Pelosi has been a favorite whipping girl of the GOP, a Democratic version of Newt Gingrich. Republicans sneer at her liberal politics and designer outfits.

Today, she's smiling and they're fuming.