(CNN) -- The race for the Democratic Party's presidential nomination remained wide open Wednesday after senators Hillary Clinton and Barack Obama split voters and delegates in the Super Tuesday primaries.
Although CNN projections showed Obama winning more states, Clinton claimed victory in several key states with higher delegate counts, including New York, which she represents in the Senate, and California.
Latest estimates suggest Clinton may have picked up only about 20 more delegates than Obama in the Super Tuesday states -- and that the pair could be separated by less than 100 delegates in all voting so far.
But it will take time to determine the final distribution of delegates because of complicated formulae, and because New Mexico's count is not yet final.
In the Republican contest, Arizona senator John McCain admitted he was the front-runner after piling up big primary wins across the country, according to CNN projections.
He is now estimated to have about half the delegates he needs to win his party's nomination, and more than Romney and Huckabee combined.
Speaking in Phoenix, Arizona, McCain expressed pleasure and gratitude over his Super Tuesday showing Wednesday and declared: "We will unite the party behind our conservative principles and move forward and win the general election in November." He said he was "pleased at the depth and breadth of our victory last night."
CNN projected McCain to win his home state, along with California, Connecticut, Delaware, Illinois, Missouri, New Jersey, New York and Oklahoma. McCain wins big; Huckabee shines
Mitt Romney was projected to take Alaska, Colorado, Massachusetts, Minnesota, Montana, North Dakota and Utah while Mike Huckabee was projected as winner in Alabama, Arkansas, Georgia, Tennessee and West Virginia.
In the Democratic races, CNN projections indicated wins for Clinton in Arizona, California, Massachusetts, New Jersey, New York, Oklahoma, Tennessee, Arkansas, where her husband, former U.S. President Bill Clinton, was once governor, and American Samoa.
Barack Obama has CNN-projected wins in his home state of Illinois, plus Alabama, Alaska, Colorado, Connecticut, Delaware, Georgia, Idaho, Kansas, Minnesota, Missouri, North Dakota, and Utah.
More than four-fifths of the 2,025 delegates needed to clinch the Democratic presidential nomination and more than 1,000 of the 1,191 necessary delegates on the Republican side were at stake on Tuesday.
The delegate count is key when looking at the results. Candidates need to notch up enough delegates -- rather than voter numbers -- to secure their party's nomination. What's next for the candidates? »
On Super Tuesday 24 states and the U.S. Pacific territory of American Samoa went to the polls -- the largest single day of voting in the nomination process.
For the Republicans, it was a day that cemented McCain's remarkable turnaround since the four-term Arizona senator, a 71-year-old former Vietnamese prisoner of war, was written off last summer as a viable White House contender by many political commentators.
But CNN Political Analyst Bill Schneider warned that McCain still faced a fight to clinch the party nomination after faring less well with traditional conservatives than with moderate Republicans. See how the analysts are calling Super Tuesday. »
"He did not carry conservative voters," Schneider said. "They are very wary of John McCain and he has to find a way to convince them that he is one of them." Watch McCain on uniting his party »
The day's biggest surprise may have been the strong showing by Huckabee, a former Arkansas governor and Baptist minister, who collected several important victories across southern states and West Virginia.
"Over the past few days, a lot of people have been trying to say that this is a two-man race. Well, you know what? It is, and we're in it," Huckabee said, reaffirming his commitment to staying in the Republican fight.
Speaking to CNN's "American Morning," Huckabee pointed out that he would support whichever candidate becomes the Republican party's nominee, including McCain, while reiterating his claim to be the most conservative candidate. Huckabee happy with his showing
Romney, who did not have any public events scheduled for Wednesday, was planning to huddle with his aides to discuss a strategy to stay in the race.
Despite outspending his rivals he received just 176 delegates from Super Tuesday, compared with at least 568 for McCain and 147 for Huckabee, according to CNN estimates.
"One thing that's clear -- this campaign's going on," Romney said Tuesday. "I think there's some people who thought that it was all going to be done tonight, but it's not all done tonight. We're going to keep on battling."
The Republican contest now shifts to to Louisiana and Washington, where voters cast ballots on Saturday, followed by polls in Maryland, Virginia and Washington D.C. next Tuesday.
Clinton, Obama trade blows
While most Republican contests are winner-take-all, most Democratic contests are awarded proportionally based on the number of congressional districts won. According to latest CNN estimates, Clinton won 569 delegates to Obama's 550 on Tuesday, giving Clinton an overall lead of 812-720.
Clinton revealed Wednesday she had dipped into her own finances for an additional boost ahead of this week's "Super Tuesday" contests, lending her Democratic presidential campaign $5 million. "I think the results last night prove the wisdom of my investment," she said. Clinton touts her victories
Campaigning in Virginia, she added: "This is a decision between two real people... People are going to have to look at us and decide who they believe would be the best president."
Speaking to reporters in Chicago, Illinois, Wednesday, Obama said: "I believe that we had an extraordinary night, it was a big victory for our campaign."
He added that this year's election is crucial because "we have a whole array of long-term challenges that demand our attention and we know we have to change the way business is done in Washington to meet them." Obama on the challenges for the next president
The Democratic contest continues Saturday with primaries in Louisiana, Washington State and Nebraska followed by primaries in Virginia, Maryland and the District of Columbia Tuesday.
CNN Political Analyst Bill Schneider predicted the Democratic contest could go all the way to the National Convention in August when delegates will gather to confirm the party's final choice. Typically, the choice of candidate is determined prior to the convention, with voting a mere formality. E-mail to a friend
CNN's Candy Crowley, Suzanne Malveaux and Mark Preston contributed to this report.