WASHINGTON (CNN) -- Former Democratic vice presidential nominee Geraldine Ferraro issued a fundraising appeal Wednesday for Sen. Hillary Clinton, more than two decades after the former New York congresswoman became the first woman to run on a major party presidential ticket.

"It's been 23 years since I was the first woman on a major party presidential slate, and I remember what it was like breaking that barrier -- including the barrage of attacks at the hands of the Republicans," Ferraro writes in an e-mail delivered by Clinton's presidential campaign. "Now Hillary is poised to break the biggest glass ceiling of them all. This time, when we elect the best, most qualified candidate for president, for the first time we'll be putting a woman in the White House."

Ferraro's e-mail comes just days before the books close on the first quarter of the 2008 primary fundraising cycle -- a benchmark in determining the early success of presidential campaigns.

Tennis superstar Billie Jean King also announced her endorsement of Clinton this morning right before the National Organization for Women was set to formally back the New York Democrat's presidential bid.