Oddly enough, Sen. Hillary Rodham Clinton, Giuliani's top Democratic rival for the White House, has the opposite history: she shifted from Republican to Democrat.
His father served time in prison for a felony assault, and later worked for his brother-in-law's loan-sharking outfit.
Will his next stop be 1600 Pennsylvania Avenue?
Early Days of Rudy Giuliani
Rudolph William Louis Giuliani III grew up in New York City, the only child of working-class parents. His father served time in prison for a felony assault, and later worked as for his brother-in-law's loan-sharking outfit. In Time's 2001 profile on Giuliani as Person of the Year, he said of his father's past, "I knew parts of it, but it was always a big secret and very shadowy. I knew he had gotten into trouble as a young man, but I never knew exactly what it was" until Barrett [a Giuliani biographer] broke the story in 2000.
In 1961, Giuliani completed high school and headed for Manhattan College in the Bronx, where he graduated in 1965. After earning his law degree in 1968 from New York University Law School, he clerked for Judge Lloyd MacMahon.
Federal Prosecutor Rudy Guiliani
Giuliani in 1970 joined the Office of the U.S. Attorney for the Southern District of New York. He went to Washington in 1975, where he served as Associate Deputy Attorney General.
Back in New York by 1977, he practiced law at the firm of Patterson, Belknap, Webb and Tyler until 1981, when he was tapped to be Associate Attorney General in the Reagan administration.
Giuliani in 1983 was named U.S. Attorney for the Southern District of New York, garnering national attention for high-profile prosecutions of Wall Street executives and organized crime figures.
The Wall Street Journal's Law Blog has credited Giuliani with patenting the "perp walk" in the 1980s-parading suspects in front of the media-and said "prosecutors have used the tool with increasing frequency, and it's picked up speed over the past half-decade. Think Enron, ImClone's Sam Waksal, and Adelphia's John Rigas."
Giuliani resigned as U.S. Attorney when President Reagan left office in early 1989, and worked for several law firms in New York.
Rudy Giuliani: Gotham's Mayor, 'America's Mayor'
Serving as mayor of New York City from 1994-2001 was perhaps Giuliani's most defining role. Sept. 11, 2001 was perhaps his most defining day in office-it was his indefatigable leadership throughout the hellish attacks and their brutal aftermath that earned him the title "America's Mayor."
"When the day of infamy came, Giuliani seized it as if he had been waiting for it all his life, taking on half a dozen critical roles and performing each masterfully. Improvising on the fly, he became America's homeland-security boss, giving calm, informative briefings about the attacks and the extraordinary response," according to Time.
Crime and welfare were other focal points of Giuliani's tenure as mayor. Under Giuliani's watch, his campaign site says, New York saw murders reduced by 66 percent, and overall crimes were slashed by 56 percent. He also helped reduce welfare rolls by about 60 percent, the site says, and transformed welfare offices into job centers.
In 1999-2000 Giuliani initiated a run for the U.S. Senate, but he withdrew from the race in May 2000, after being diagnosed with prostate cancer.
Businessman and Presidential Candidate
His mayor-days done, Giuliani started Giuliani Partners, a consulting business for which he serves as chairman and CEO. In 2005 he joined the Bracewell & Patterson law firm-subsequently renamed Bracewell & Giuliani.
A May 13 Washington Post article says Giuliani's gross assets in 2001 were between $1.16 million and $1.83 million. The success of Giuliani Partners, according to the story, transformed him "from a moderately well-off public servant into a globe-trotting consultant whose net worth is estimated to be in the tens of millions of dollars."
Earlier this year he declared his candidacy for President of the United States in the 2008 election.
Rudy Giuliani’s History: Highlights of his Life and Career
1944 - born in Brooklyn, New York
1961 - graduates from Bishop Loughlin Memorial High School
1965 - graduates from Manhattan College
1968 - graduates cum laude from New York University Law School
1970 - joins the Office of the U.S. Attorney for the Southern District of New York
1975 - heads to Washington to serve as Associate Deputy Attorney General
1977 - practices law in New York
1981 - tapped as Associate Attorney General in the Reagan administration
1983 - named U.S. Attorney for the Southern District of New York
1989 - resigns post as U.S. Attorney; makes first run, unsuccessfully, for mayor of New York City; practices law in New York
1993 - elected mayor of New York, beating incumbent David Dinkins
1997 - re-elected to second term as mayor
1999 - 2000-campaigns for U.S. Senate; withdraws in May 2000 due to prostate cancer
2002 - launches Giuliani Partners, a consulting firm
2005 - joins the Bracewell & Patterson law firm, subsequently renamed Bracewell & Giuliani
2007 - announces intentions to run for president in the 2008 election
This report is based on a compilation of facts and background from the following sources:
Rudy Giuliani (Wikipedia.org)
Breaking Down the "Perp Walk" (Wall Street Journal's Law Blog)
Giuliani 'not confident' war will turn around (CNN.com)
Rudolph W. Giuliani (The New York Times reference page)
CNN Election Center 2008
Giuliani Partners Web site
Bracewell & Giuliani