Kerry had considered making a presidential run in 2000, but ruled out a bid for the White House on February 26, 1999, stating that "the time is not right."  In 2001 and through to November 2002, he indicated that he would likely make a White House bid, while avoiding any outright declaration in deference to his '02 re-election campaign. 

On December 1, 2002, appearing on NBC's "Meet the Press," the Massachusetts senator announced formation of an exploratory committee.  From the start, Kerry was one of the frontrunners in a crowded Democratic field, in large part because his service in Vietnam offered a basis upon which to stand up to President Bush on defense and security issues.  However, Kerry's support of the resolution on Iraq was not popular among some Democrats, and former Vermont Gov. Howard Dean was able to use that issue, a blunt, plainspoken style, and an insurgent, Internet savvy campaign to build a very competitive challenge for the nomination.  Kerry's campaign downplayed the buzz surrounding Dean, saying that their goal is to peak at the right time.  On September 2, 2003, in front of the USS Yorktown in Charleston, South Carolina, Kerry formally announced his candidacy declaring, "I believe that the courage of Americans can change this country." 

Kerry's campaign appeared to be seriously faltering.  In November he replaced campaign manager James M. Jordan with Mary Beth Cahill, who was serving as Sen. Edward M. Kennedy's chief of staff.  A December 3, 2003 American Research Group poll of likely Democratic primary voters in New Hampshire showed Kerry trailing Dean 45% to 13%.  (New Hampshire, with its first in the nation primary, was supposed to give Kerry, from the neighboring state of Massachusetts, a boost).  At the end of December Kerry loaned his campaign over $6 million, secured through a mortgage on his share of the family's home in Boston. 

With Kerry lagging in New Hampshire, the campaign turned its focus to the Iowa caucuses.  Under the leadership of Iowa state director John Norris, a former congressional candidate, and strategist Michael Whouley, the campaign built up a top notch field organization.  While Dean secured a number of high profile endorsements including former Vice President Al Gore (Dec. 9, 2003) and former Sen. Bill Bradley (Jan. 6, 2004), Sen. Tom Harkin (Jan. 9, 2004), Kerry led in endorsements by state legislators.  In December and January, Kerry spent more time in the state than any other candidate.  Veterans provided an important edge.  In the closing days of the Iowa campaign, Dean campaign's orange-hatted Perfect Storm swept the state but on Caucus Night, January 19, Kerry prevailed, securing 37.09% of the delegates to county conventions; Sen. John Edwards came in second and Dean third.  Eight days later Kerry again came in first in the New Hampshire primary with 38.39% of the vote, and from then on he never looked back.  Edwards, his last major challenger, withdrew after the March 2 contests.

Kerry had announced his decision to forego federal matching funds on November 14, following the lead of the Dean campaign.  In March, with Kerry now the presumptive nominee, the campaign achieved extraordinary, record-breaking fundraising successes, bringing in $44.2 million in March, $31.3 million in April, $30.8 million in May, and $36.5 million in June.  During this time the Bush campaign spent tens of millions of dollars seeking to define Kerry ("wrong on defense," "raising taxes is a habit of Kerry's," "playing politics with national security," and so forth).

There remained the question of who Kerry would pick as his running mate.  Sen. John McCain (R-AZ) figured in some early speculation, but heading into July Sen. Edwards, Rep. Dick Gephardt (MO) and Gov. Tom Vilsack (IA) were most prominently mentioned; on July 6 Kerry announced his selection of Edwards.  Democrats and many pundits responded positively, noting Edwards adds geographic balance as well as a bit of life to the campaign.  (A significant theme in the news coverage of the time suggested that voters have not "warmed up to" Kerry).  Conservatives, however, were quick to apply the liberal label to the Kerry-Edwards ticket. 

In his acceptance speech at the convention in Boston, Kerry declared that "...we are here tonight united in one simple purpose: to make America stronger at home and respected in the world."  The convention did not generate much of a bounce in the polls.  Kerry's campaign had earlier pointed out that the relatively small number of undecided voters made a sizable bounce unlikely.  Nonetheless a post-convention memo ("From Small Bounce to Big Opportunity") from the Democracy Corps (James Carville, Stanley Greenberg >), while acknowledging some accomplishments, stated that the "small shift in the vote is disappointing." 

From Boston, Kerry and Edwards embarked on a "Believe in America" tour, and the final three months of the campaign will see an intense focus on about 20 battleground states.