BOSTON — Geraldine Ferraro was a relatively obscure congresswoman from the New York City borough of Queens in 1984 when she was tapped by Democratic presidential nominee Walter Mondale to join his ticket.

Her vice-presidential bid, the first for a woman on a major party ticket, emboldened women across the country to seek public office and helped lay the groundwork for Hillary Rodham Clinton's presidential candidacy in 2008 and John McCain's choice of his running mate, Sarah Palin, that year.

Ferraro died Saturday in Boston, where the 75-year-old was being treated for complications of blood cancer. She died just before 10 a.m. local time, said Amanda Fuchs Miller, a family friend who worked for Ferraro in her 1998 Senate bid and was acting as a spokeswoman for the family.

Mondale's campaign had struggled to gain traction and his selection of Ferraro, at least momentarily, revived his momentum and energized millions of women who were thrilled to see one of their own on a national ticket.

The blunt, feisty Ferraro charmed audiences initially, and for a time polls showed the Democratic ticket gaining ground on President Ronald Reagan and Vice-President George H. W. Bush. But her candidacy ultimately proved rocky as she fought ethics charges and traded barbs with Bush over accusations of sexism and class warfare.

Ferraro later told an interviewer, "I don't think I'd run again for vice-president," then added "Next time I'd run for president."

Reagan won 49 of 50 states in 1984, the largest landslide since Franklin D. Roosevelt's first re-election over Alf Landon in 1936. But Ferraro had forever sealed her place as trailblazer for women in politics.

"At the time it happened it was such a phenomenal breakthrough," said Ruth Mandel of the Center for American Women in Politics at Rutgers University. "She stepped on the path to higher office before anyone else, and her footprint is still on that path."

Palin, who was Alaska's governor when she ran for vice-president, often spoke of Ferraro on the campaign trail.

"She broke one huge barrier and then went on to break many more," Palin wrote on her Facebook page Saturday. "May her example of hard work and dedication to America continue to inspire all women."

For his part, Mondale remembered his former running mate as "a remarkable woman and a dear human being."

"She was a pioneer in our country for justice for women and a more open society. She broke a lot of moulds and it's a better country for what she did," Mondale told The Associated Press.

Ferraro died at Massachusetts General Hospital, where she had gone Monday for a procedure to relieve back pain caused by a fracture. Such fractures are common in people with her type of blood cancer, multiple myeloma, because of the thinning of their bones, said Dr. Noopur Raje, the Mass General doctor who treated her.

Ferraro, however, developed pneumonia, which made it impossible to perform the procedure, and it soon became clear she didn't have long to live, Raje said. Since she was too ill to return to New York, her family went to Boston.

Raje said it seemed Ferraro held out until her husband and three children arrived. They were all at her bedside when she passed, she said.

"Gerry actually waited for all of them to come, which I think was incredible," said Raje, director of the myloma program at the hospital's cancer centre. "They were all able to say their goodbyes to Mom."

Ferraro stepped into the national spotlight at the Democratic convention in 1984, giving the world its first look at a co-ed presidential ticket. It seemed, at times, an awkward arrangement -- she and Mondale stood together and waved at the crowd but did not hug and barely touched.

Delegates erupted in cheers at the first line of her speech accepting the vice-presidential nomination.

"My name is Geraldine Ferraro," she declared. "I stand before you to proclaim tonight: America is the land where dreams can come true for all of us."

Her acceptance speech launched eight minutes of cheers, foot-stamping and tears.

Ferraro, a mother of three who campaigned wearing pastel-hued dresses and pumps, sometimes overshadowed Mondale on the campaign trail, often drawing larger crowds and more media attention than the presidential candidate.

But controversy accompanied her acclaim.

A Roman Catholic, she encountered frequent, vociferous protests of her favourable view of abortion rights.

She famously tangled with Bush, her vice-presidential rival who struggled at times over how aggressively to attack Ferraro.