Democrat John Edwards and Republican Rudy Giuliani abandoned their US presidential bids today, narrowing the field in both parties to two main candidates ahead of next week's big multi-state nominating contest.
Former New York Mayor Mr Giuliani dropped out of the race tonight and endorsed his former rival, Senator John McCain of Arizona.
Mr Giuliani, in a strategic move, decided not to campaign heavily in the early primary states and instead concentrated his efforts on Florida, hoping for a strong showing in the fourth most-populous US state.
Instead, his absence from the early primary states appeared to hurt his campaign and he ended up finishing a disappointing third in Florida behind Mr McCain and former Massachusetts governor Mitt Romney.
The 63-year-old former mayor gained national prominence in 2001 for his role after the September 11th attacks and made that experience the centerpiece of his presidential candidacy.
While Mr Giuliani's decision was widely expected, Mr Edwards' move came as a surprise. He had vowed just last week to stay in the race until next Tuesday, when almost half the US states vote on candidates for the November election.
The withdrawal of Mr Edwards, who campaigned as the champion of low- and middle-income families, left former first lady Hillary Clinton facing Illinois Senator Barack Obama for the Democratic nomination in what seemed likely to be a long, bruising struggle.
"It is time for me to step aside so that history can blaze its path,"
Mr Edwards, a former North Carolina senator, told supporters in a New Orleans neighborhood devastated by Hurricane Katrina in 2005, the same place where he launched his campaign.
Regardless of whether Mr Obama or Ms Clinton wins, Democrats will field a history-making ticket, the first time a major US political party has had a black or a woman as a presidential candidate.
"We do not know who will take the final steps to 1600 Pennsylvania Avenue, but what we do know is that our Democratic Party will make history ... and with our convictions and a little backbone we will take back the White House in November," Mr Edwards said.
Mr Edwards did not immediately endorse either of his rivals.
Mr Obama and Ms Clinton, a New York senator, both surveyed the new political landscape and began angling for an edge. Both echoed Edwards' theme of ending poverty. Obama cast himself as the best candidate to take on John McCain, the clear Republican front-runner after his victory on Tuesday in Florida.
"We need to offer the American people a clear contrast on national security, and when I am the nominee of the Democratic Party, that's exactly what I will do," Mr Obama told a crowd of 18,000 in Denver, saying Clinton had voted with McCain to authorize the Iraq war.
The candidates are in the early stages of a state-by-state battle to pick Republican and Democratic presidential nominees. The winners from the two parties will face off in the November election to succeed President George W. Bush.
Mr Edwards' withdrawal coincided with media reports that former New York Mayor Giuliani would abandon his own presidential bid and endorse McCain, the Arizona senator.
That would leave McCain facing a strong challenge by former Massachusetts Gov. Mitt Romney. Former Arkansas Gov. Mike Huckabee is still formally in the race but his lack of campaign money and limited appeal beyond Christian conservatives has left him
trailing far behind.