A nail-biter of a fight for the Democratic presidential nomination enters its biggest day Tuesday, with voters in 22 states and American Samoa casting ballots in a historymaking race.
Polls released over the weekend show Sen. Hillary Rodham Clinton, long the national Democratic front-runner, losing ground. In just the past few days, Sen. Barack Obama has pulled even in key states long seen as Clinton country, among them California, New Jersey, and Missouri.
The tightness of the race increases the odds that the battle for the nomination will stretch past Tuesday into the more than a dozen states voting in mid-February and early March.
Still, it is hard to overstate the significance of the voting Tuesday: About 83 percent of delegates needed for the nomination are up for grabs. With the withdrawal last week of former Sen. John Edwards, Super Tuesday offers the first one-on-one showdown between the front-runners.
Recent days have seen the lead candidates and their surrogates in a frantic coast-to-coast hunt for votes. With her large lead in delegate-rich California gone as of the weekend, according to several polls, Senator Clinton dispatched her husband, President Bill Clinton, there for two days while she traveled to Missouri, Minnesota, Connecticut, and Massachusetts.
She bought an hour of airtime on the Hallmark Channel Monday night for a "Voices Across America" town-hall meeting.
On Sunday, California's first lady, Maria Shriver, endorsed Senator Obama at a Los Angeles rally featuring two other supporters – Oprah Winfrey and Caroline Kennedy – expected to help him cut into Clinton's support among women. Obama spent the weekend in Idaho, Minnesota, Missouri, and Delaware and was scheduled Monday to visit New Jersey, Connecticut, and Massachusetts.
For both candidates, the road to Super Tuesday has been long and hard-fought. The primary season opened early and wide, with eight Democratic candidates vying for the nomination before contests in Iowa, New Hampshire, Nevada, and South Carolina whittled the field to two.
Shrewd campaigners who raised more than $100 million apiece last year, Clinton and Obama each won a pair of the four contested primaries thus far.
Seldom have two hopefuls entered the biggest day of voting on such seemingly equal footing. Never before has either a woman or an African-American been this close to either party's nomination.
Clinton, with her high name recognition in Democratic politics, had led in the national polls for more than a year. But the second-term senator and former first lady, who has cast herself as the battle-tested candidate of experience, has faced unexpectedly stiff head winds since Obama's victory in Iowa on Jan. 3.
Obama, a first-term Illinois senator, put together vibrant grass-roots organizations in early-voting states, where he invested months on the ground introducing himself to voters with stirring oratory and a theme of hope. His challenge Tuesday will be battling the Clinton name in states that know him less well and where television ads play a bigger role than the grueling shoe-leather politics he parlayed into victories in Iowa and South Carolina.
"What you had with these early states are important stakeholders in the Democratic Party" – left-leaning independents, blacks, young voters – "but not necessarily the real center," says Robert Stein, a political scientist at Rice University in Houston. The Feb. 5 sweepstakes "is probably a more representative sample of what the Democratic Party looks like."
Obama raised a record $32 million in January, enough to advertise in 20 of the 22 states voting Tuesday and a half dozen states beyond.
Because most states award Democratic delegates in proportion to the vote for each candidate, it is unlikely that either Clinton or Obama will win enough delegates Tuesday to clinch the nomination. But one or the other could emerge with a clear advantage, making it a matter of time before that momentum jells into hard numbers in later contests.
If neither wins a majority before the Democratic National Convention in August, the race could turn on 796 so-called "superdelegates" – governors, Congress members, and other party leaders – who are not bound by the popular vote and whose support both camps have aggressively courted.
Clinton has led with superdelegates, who make up one-fifth of the voting pool at the conventions. But Obama's endorsement last week by Sen. Edward Kennedy of Massachusetts, a Democratic stalwart with pull across the party base, is expected to narrow her lead.
Clinton built her Feb. 5 strategy around four states: California, where 370 delegates are up for grabs; New York, with 232 delegates, where she is senator; New Jersey, home to many New York commuters; and Arkansas, where she was first lady.
Obama is counting on a decisive victory in his home state of Illinois, with 153 delegates, but is otherwise taking broader aim across the electoral map. His campaign is targeting "red states" in the heartland, where voters may be wary of Clinton. It is also putting its organizational muscle to work in six states holding caucuses Tuesday, including Minnesota, where Obama's ads tap into strong antiwar sentiment.
Feb. 5 "is quite likely to be muddled," says Lawrence Jacobs, a political scientist at the University of Minnesota in Minneapolis. Victories in places like Kansas, Idaho, and Colorado, he says, "would add a clear story line where Obama can talk about winning in parts of the country, including the upper Midwest, which will clearly be a battleground in the general election."
Though voters are split between the Democratic front-runners, they mostly agree on their top issue: the economy. A race that looked at first like a referendum on the Iraq war is increasingly focused on healthcare costs, job security, and the mortgage crisis.
In a debate in Los Angeles Thursday, Obama invoked the fight against poverty championed by his onetime rival, Senator Edwards. The next day he held an "economic summit" in New Mexico, one of the states with a Democratic caucus Tuesday.
A new Clinton ad in Super Tuesday states shows a parachutist in free fall and the word "recession" as an announcer intones, "With your job and family security in the balance, the stakes have never been higher in choosing our new president."
The candidates' views on economic issues – particularly differences on healthcare – may be pivotal for some voters. But another potent theme will be electability, some analysts say.
With Sen. John McCain now the GOP front-runner after victories in New Hampshire, Florida, and South Carolina, Democratic voters may also try to assess which candidate has the best chance against him in the general election.