Less than a year ago, John McCain's chances of winning the Republican presidential nomination seemed like a pipe dream. But on Tuesday, the tenacious Arizona senator finally secured the GOP presidential nomination with wins in Vermont, Rhode Island, Ohio and Texas, pulling off one of the most dramatic political resurrections in recent memory.

On the Democratic side, as recently as December, Ohio was supposed to be a bit of Midwestern icing on Senator Hillary Clinton's presidential nomination cake. Instead, the state became a must-win for a campaign that had improbably tumbled from a sure thing to walking wounded. After weeks of hitting rival Democratic Senator Barack Obama with harsh TV ads and forcing him into one of his campaign's first major stumbles over an aide's claims regarding his stance on NAFTA, Clinton did more than survive, she handily beat Obama in Ohio by a 54 to 44 margin (with 99 percent of precincts reporting), then, much, much later in the night, tacked on a major projected win in the Texas primary for proof that her campaign still had plenty of fight left in it.

But early Tuesday night, it was Obama who made it an even dozen wins in a row when he was the projected winner in the liberal-leaning state of Vermont, beating Clinton 60 percent to 38 percent to take most of the state's 17 delegates. Clinton topped the other New England contest, winning in Rhode Island 58 percent to 40 percent, according to CNN, breaking Obama's winning streak and signaling a revival of a campaign that some pundits believed could possibly fold up its tent as early as Wednesday.

Standing under a rain of confetti, Clinton celebrated her Ohio victory with a raucous rally in Columbus. Onstage with her was daughter Chelsea, but, tellingly, not former President Bill Clinton, who was campaigning elsewhere but has been flying under the radar since his spate of negative campaigning earlier this year was perceived to have hurt her image.

"For everyone here in Ohio and across America who's ever been counted out but refused to be knocked out and for everyone who has stumbled but stood right back up and for everyone who works hard and never gives up, this one is for you," Clinton said, beaming. "You know what they say, as Ohio goes, so goes the nation. Well, this nation's coming back, and so is this campaign," she added, vowing to go "all the way" as her jacked-up supporters snatched a page from the Obama playbook and chanted, "Yes, she will!" And, in keeping with the hard-hitting message that appears to have secured her Buckeye State victory, Clinton warned, "Protecting America is the first and most urgent duty of the president. When there's a crisis and that phone rings at 3 a.m. in the White House, there's no time for speeches or on-the-job training. You have to be ready to make a decision."

According to CNN, the Obama campaign downplayed the Clinton win in Ohio, saying that the slim margin of victory was less impressive given her 20-point lead as recently as a few weeks ago and that it was hardly a sign of momentum. They also pointed to the negative tone the Clinton campaign has taken in the past two weeks, including the now-infamous "red phone" commercial about national security, which the Obama camp dismissed as fear-mongering, although it appeared to win over a number of voters who were undecided up until the past three days.

With 99 percent of the vote in at press time, CNN projected that Clinton would also win the Texas primary by a slim margin, 51 percent to 48 percent, garnering 1,452,776 votes to Obama's 1,354,553. With just 5 percent of the caucus vote in, Obama led in that contest, though it was feasible that even if Clinton holds on to her lead in the popular vote, she could end up with fewer delegates in the state once they are portioned out. And either way, Obama is still likely to hold a slim delegate lead once all the votes are sorted out.

The victories in Ohio and Texas for Clinton, however, give her bragging rights in terms of wins in nearly all the largest states to hold primaries to date, including California, New York and New Jersey.

Telling supporters in San Antonio that no matter what happened Tuesday night, he would hold the same delegate lead and is still on his way to the nomination, Obama spoke of his dream of building a coalition of voters that crosses barriers of race, gender, age and party. This movement, he said, could potentially turn the page on the politics "that has shut us out, let us down and told us to settle," he said. "We could write a new chapter in the American story. We were told this wasn't possible. We were told the climb was too steep. We were told our country was too cynical, that we were just being naive, that we couldn't really change the world as it is."

Like Clinton, Obama looked forward to the coming weeks, during which he said he would begin a "great debate about the future of this country," not with his Democratic rival, but with McCain, whom he praised, but claimed had fallen in line "behind the very same policies that have ill-served America."

McCain was put over the top on the Republican side with projected wins in Vermont by a 72 percent to 14 percent margin over former Arkansas Governor Mike Huckabee, as well as in Ohio, where CNN said he was projected to beat Huckabee 60 percent to 31 percent and take all 88 delegates. Huckabee announced his exit from the race on Tuesday and endorsed McCain.

The determined politician conceded to McCain shortly after 9:15 p.m. ET, saying that he had already called to congratulate the party's nominee and committed to helping the senator unite the Republican Party. Speaking to supporters in Irving, Texas, Huckabee also thanked McCain for running an honorable campaign and staying above the fray in a hard-fought battle. "I believe tonight that one of the things we'll be able to say is not only that we fought the good fight and finished the race," said Huckabee, paraphrasing the apostle Paul. "We'd like to have finished it first, but we stayed in until the race was over, but more importantly we kept the faith. And that for me has been the most important goal of all. I'd rather lose an election than lose the principles that got me into politics in the first place."

Standing near a giant sign that read "1,191," McCain celebrated his long-sought, hard-fought campaign victory by vowing to defend the decision to go to war in Iraq and finding a way to leave that country in victory and security, even as he admitted that he never believed he was destined to be the commander in chief. "I am very grateful for the broad support you have given our campaign, and I am very, very grateful and pleased to note that tonight, my friends, we have won enough delegates to claim with confidence, humility and a great sense of responsibility that I will be the Republican nominee for president of the United States," he said, thanking not just his Republican supporters, but also independents and "independent-minded" Democrats who helped him avenge his failed 2000 presidential-nomination defeat.

"Now we begin the most important part of our campaign, to make a respectful, determined and convincing case to the American people that our campaign and my election as president, given the alternatives presented by our friends in the other party, are in the best interest of the country we love." And though he stated emphatically that his campaign will be about more than "another tired debate of false promises, empty sound bites or useless arguments from the past that address not a single of America's concerns for their family's security," he wasted no time in lashing Obama and Clinton over their recent statements that they would consider renegotiating the NAFTA trade treaty with Mexico and Canada. He also called out the Democrats' determination to return to the "failed big-government mandates of the '60s and '70s to address problems such as the lack of health care insurance for some Americans."

Gritting his teeth, McCain ended the address by challenging his supporters to "stand up with me, my friends. Stand up and fight for America. For her strength, her ideals and her future. The contest begins tonight."

Throughout the night, all eyes were on the race in Ohio, which was expectedly close, as well it should have been, given that Democratic candidates spent mightily on advertising in the Buckeye State, with Obama reportedly lavishing nearly $2.8 million on TV advertising alone and Clinton dropping close to $1.5 million. In addition, thousands of volunteers between the two spent the past few days knocking on a million doors and phoning millions of voters, according to the Cincinnati Enquirer.

Once again, young voters were a key demographic, with exit polls of 18- to 29-year-olds in Ohio solidly in Obama's column by 61 percent to 35 percent, while the Washington Post's exit polls had Obama carrying the black vote in Ohio by a 9-to-1 margin. CNN reported that the patterns were similar in Texas, with young voters going to Obama 58 percent to 42 percent, while Clinton led among voters 60 and older by 64 percent to 33 percent.

Despite her own husband saying several weeks ago that the whole nomination process was coming down to must-wins Ohio and Texas — a statement the Clinton campaign has since downplayed — Hillary Clinton urged voters to settle in for what is likely to be a long, long battle, according to The New York Times.

"You know, this is a long process," Clinton told reporters Tuesday morning outside a Houston polling place. Her campaign was already talking about the April 22 primary in Pennsylvania, where Clinton is currently a favorite. Meanwhile, the paper said that Obama's camp was working behind the scenes to persuade Democrats, especially the all-important superdelegates who will likely decide the race, to begin falling in place behind him as early as Wednesday. Looming above all this jockeying was the harsh reality that even if either candidate ran the table on the remaining contests, CNN projected that neither could secure enough delegates to win the 2,025 needed for the nomination.

Sensing victory on the horizon, McCain eased up on the gas over the weekend, inviting reporters to his Arizona home for a barbecue instead of campaigning as polls had him with comfortable, mostly double-digit leads over fading opponent Huckabee.

When McCain clinched the nomination, balloons came down and Chuck Berry's "Johnny B. Goode" blasted from the speakers. His team also broke out jackets touting the road to Minneapolis (the site of the Republican convention). According to CNN, President Bush will endorse the 71-year-old Arizona senator on Wednesday at 1:15 p.m. ET from the White House. The endorsement could be a major boost for the campaign, which continues to struggle to win over a majority of the core conservative base.

The next contest for the Democrats is the Wyoming caucus on Saturday and then the Mississippi primary on Tuesday, with the slugfest likely to continue until the final primary in Puerto Rico in early June, the last vote before the August Democratic convention in Denver. With her wins on Tuesday, Clinton has almost assured that the nominee will be decided at the convention and that the all-important superdelegates will be called on to break the deadlock.

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[This story was originally published at 9:40 p.m. ET on 03.04.08]