Just a few years ago, Republicans greeted Nancy Pelosi's rise to the upper echelons of the Democratic party as a political gift.

She was, her rightwing foes asserted, an extreme liberal of the kind true Americans just don't like – vocal in her support of gay rights, feminist causes and policies frequently branded as socialism.

Worst of all in the wake of the 9/11 attacks, she was strongly against the invasion of Iraq, just as she had been opposed to the earlier war with Baghdad over Kuwait. Republicans smirked that the Democrats had doomed themselves to irrelevance when they chose Pelosi as the first woman to lead them in the House of Representatives in 2002, and later as Speaker.

Not a few in Pelosi's own party and beyond agreed. Among other things, she had a reputation for shooting her mouth off, once calling the elder President Bush a "jerk". She would come to say much worse about his son.

Joe Klein, author of the bestselling political novel Primary Colors, described the newly elected Democratic leader in the larger of the two houses of Congress as "the very sort of political anachronism the party should studiously avoid".

Eight years on, Pelosi is once again the favoured target for Republican attacks after rescuing President Obama's healthcare legislation as it teetered on the brink of oblivion. But there are not many who now call her an anachronism or accuse her of marginalising her party.

Through several elections and an unpopular war, Pelosi has been instrumental in leading the Democrats back to control of the House of Representatives and then on to a healthy majority. And now, after forging the consensus among deeply divided House Democrats that saw passage of the first significant, if compromised, social legislation in decades, Pelosi is being heralded as the most powerful woman in American history and the most powerful Speaker of the House of Representatives in a century.

It's not an accolade she rejects.

"That sounds good. I don't take it personally, except I take it as a compliment for all women because as the first woman Speaker I certainly wanted to demonstrate that we could get a job done that has eluded others for a century," she told ABC news this week.

Pelosi has been honing the skills to get the job done almost since the day she was born 70 years ago.

She wasn't elected to public office until she was 47, but Pelosi grew up in a deeply political household in the Italian quarter of Baltimore. Her father, Thomas D'Alesandro, was a member of Congress and later Baltimore's mayor.

D'Alesandro was a vigorous supporter of Franklin Roosevelt's social justice programmes and believer in the power of government to improve the lives of people who needed the help most.

Pelosi watched her father's political machine at work – seeing how favours were delivered, loyalties built up and debts called in, and how that could be put to the public good. They were lessons she carried to school, where she told her classmates how their parents could make the system work for them. "I would tell them how to get a sick relative into City hospital, how to get a job that paid a living wage," Pelosi told the Nation in 2001. "I thought that was what it meant to be a Democrat: You make sure that government works for the people."

Pelosi's father also steeped her in the art of the compromise, and when to stand her ground. Those lessons were not to be unleashed until several years later after she married a multimillionaire financier, moved to San Francisco and became embroiled in Democratic Party politics between raising five children.

Pelosi built a reputation for two complementary strengths: forging constituencies among the disparate Democratic Party interests in northern California, and as a formidable fundraiser. Those talents helped propel her to the regional party leadership and then, in 1987, positioned her well to win a seat in Congress that she has held on to through 10 elections, winning by sizeable majorities.

Once in Washington, Pelosi kept the financial ball rolling on behalf of the party and other members of Congress, not only bringing in more than $100m over the years but also winning friends who would prove valuable during her rise in the House.

Pelosi won the post of whip in 2001 at the expense of Steny Hoyer, who has found himself trailing Pelosi ever since. A year later she became her party's leader in the House and set about forging an unusual degree of unity among Democrats while annoying Republicans.

In recent months, the Democrats have routinely accused the Republicans of being the party of 'No': of resisting legislation without offering viable alternatives. Nowhere was this clearer than over healthcare, when Republicans in both houses of Congress voted solidly against the reforms.

But it was the strategy Pelosi pursued when the Democrats found themselves in opposition.

When President George Bush proposed to reform social security, Pelosi pressed Democrats to avoid a public debate over the issue because it would be hard to win against the pulpit of the presidency. She offered no alternative plan and instead preferred to direct the party's energies in to unleashing a full frontal attack on Bush's motives. Social security reform failed.

Pelosi demanded, and frequently got, a unified front in opposition to other Republican legislation. She rarely defeated it but did force more moderate Republicans to vote with conservative members of their own party in order to pass cuts to public health and other social programmes. When election time came, Democrats were able to brand most Republicans with the same iron of serving only the rich and special interests.

Pelosi even barred Democrats from holding joint press conferences with Republicans.

She was also notoriously outspoken and, at times, seemingly out of step with the mood of America. She vigorously opposed the invasion of Iraq, leading Newsweek to describe her leadership as making "the Democratic caucus look more dovish than even the French".

Just ahead of Bush's resounding 2004 presidential election victory, Pelosi launched a vitriolic attack on the president in the San Francisco Chronicle.

"Bush is an incompetent leader. In fact, he's not a leader. He's a person who has no judgment, no experience and no knowledge of the subjects that he has decided upon," she said. "Not to get personal about it, but the president's capacity to lead has never been there. In order to lead, you have to have judgment. In order to have judgment, you have to have knowledge and experience. He has none."

To some that made her look like an extreme ideologue. But by the time Bush left office, much of America had come around to thinking that Pelosi had a point. And by then, the Democrats had won control of the House of Representatives again, and Pelosi was the first woman Speaker.

Republicans are frustrated that while Pelosi is not popular with Americans – no Congressional leader ever is – they have not grasped just how far to the left she is by US standards. Pelosi would not disagree. In 1996, she told the San Francisco Chronicle: "I don't consider myself a moderate."

The right sees her as a radical feminist for stands such as taking on the notoriously prejudiced Senator Jesse Helms to his face when he blocked a treaty against discrimination against women.

Pelosi has also been an ardent advocate of gay rights, which is no great surprise seeing as she represents a San Francisco constituency in Congress. She brought the parents of a Wyoming student who was tortured and murdered because he was gay to the 2000 Democratic party convention, helping to lay the ground for the passage of hate crime legislation.

Last year, Pelosi drew fire after she got into a public spat with the CIA over the extent to which she was briefed, as the most senior Democrat on the intelligence committee, about the waterboarding of suspected terrorists.

"In that or any other briefing‚ we were not, and I repeat, were not told that waterboarding or any of these other enhanced interrogation techniques were used," she said.

The CIA said she was told and did not object. The former House Speaker, Newt Gingrich, accused Pelosi of lying.

"I think she has lied to the House, and I think that the House has an absolute obligation to open an inquiry, and I hope there will be a resolution to investigate her," he told ABC news. "I think this is the most despicable, dishonest and vicious political effort I've seen in my lifetime …

"She is a trivial politician, viciously using partisanship for the narrowest of purposes, and she dishonours the Congress by her behaviour."

Pelosi rode the storm, in part because the CIA later admitted to misleading Congress over other aspects of Bush's war on terror.

"She is on the far left of her caucus on most issues," said Jeremy Mayers, a political science professor at George Mason University. "She represents a very leftwing district out in San Francisco. The protests that Nancy gets in her district are about her being too conservative.

"Her district is so far off the map of heartland politics. But what she has done very well is transition herself so that she is able separate her own political opinions from the job of leader. She's a woman of the left, she still has very strong political views. But she has not put her own political views ahead of her job as Speaker of the House."

That positioned her well when Obama came to power, and never more so than over healthcare.

Pelosi drew on her seven decades of political tuning and her detailed knowledge of what makes individual members of the House tick to bridge what at times appeared to be looming chasms between the liberal bloc, "Blue Dog" conservative members, the Black caucus and members of the House beholden to special interests over issues such as the cost of reform, the degree of government intervention and the ever present wrangling over abortion.

It wasn't easy. Some female members of Congress were furious with Pelosi for "throwing women under the bus" by agreeing to tight restrictions on insurance coverage of terminations.

But Pelosi commands loyalty and she won House members over the way she has long operated, vote by vote – contacting a prominent priest to help reassure those wavering over abortion – until she was sure of more than the 216 votes needed to pass the legislation.

Pelosi's success was not only in gathering the votes when there were many who thought healthcare reform was dead after the Democrats lost Ted Kennedy's old Senate seat earlier this year. The House Speaker played a crucial role in keeping Obama on track for wholesale reform when the president was edging toward piecemeal changes because of the political setbacks.

As Obama wavered, Pelosi declared that the struggle was far from over. "You go through the gate. If the gate's closed you go over the fence. If the fence is too high, we'll pole-vault in. If that doesn't work, we'll parachute in. But we are going to get healthcare reform passed for the American people," she said.

That meant steering around Obama's attempts to reach a bipartisan agreement with the Republicans intent on scuppering the legislation as a means of politically neutering the presidency. "You strive for bipartisanship when you can," Pelosi told ABC news after the healthcare bill passed. "But you cannot let the lack of bipartisanship stand in the way of making this change that is important to the American people."

Mayer said Pelosi read the political map exactly right. "This was a great triumph of the inside game, of the vote counting, of understanding exactly how far she could go," he said.

But there are those who question the characterisation of Pelosi as the most powerful House Speaker of the past century. Larry Sabato, a political scientist at the University of Virginia, points to Sam Rayburn, who wielded an iron grip on Congress in the middle of the last century, and Tip O'Neill, who faced down Ronald Reagan.

"Pelosi is fortunate to have a large Democratic majority that is overwhelmingly liberal and a Democratic president who is in tune with her. I'm not minimising the accomplishment. She deserves credit. But mostly it was the voters who did it by electing liberals," he said. "Nancy Pelosi has become one of the most divisive politicians in the country. Look at her polls. She is widely disliked. People hate Congress and she's the face of it. That's going to limit her."

That is precisely what the Republicans hope to exploit in November's mid-term election. In their latest attack advert, Pelosi is pictured in flames alongside a demand to "Fire Pelosi" by overturning the Democratic majority in the House of Representatives. It has brought in $1.5m to the Republican campaign chest as the backlash grows.

Pelosi's own seat is safe but after persuading Democrats to follow her into the minefield, her challenge is to keep them in Congress and herself in power.

CV: Speaker Nancy Pelosi



Born

Family Her late father, Thomas D'Alesandro Jr, was a Democratic congressman and Baltimore mayor. Her brother, Thomas D'Alesandro, also went on to be mayor of Baltimore.

Personal life Married to Paul Pelosi. Five children: Nancy Corinne, Christine, Jacqueline, Paul and Alexandra, and seven grandchildren.

Education

Trinity College, Washington DC

Career

1976-1996 Democratic National Committeewoman from California.

1981-1983 Chair, California State Democratic party.

1985-1986 Finance chairman, Democratic senatorial campaign committee

1987-present Elected as a Democrat to Congress, by special election, following the death of representative Sala Burton. Has been re-elected as representative of California's Eighth District to the 11 succeeding Congresses.

2001 House Democratic whip

2002 Elected Democratic leader of the House, making her the first woman to lead a major political party in the US.

2007 Made history by becoming the first woman to serve as Speaker of the house. Currently in her second term in the position.

Areas of interest

A promoter of healthcare, she spearheaded Obama's reforms through the house. She describes climate change as her "flagship issue".

Honours

Ranked 35th in Forbes magazine's 100 most powerful women.

Time's person of the year 2009.

What they said

"An extraordinary leader for the American people" (Barack Obama)

"One of the strongest and most effective Speakers in decades" (Thomas Mann, Brookings Institution)

Holly Bentley