John Kerry (search) emerged from decisive victories in Virginia and Tennessee on Tuesday night with what could be the final spark needed to hurl his campaign out of the primaries and into the general election.

Kerry proved that he has the goods to take the South, a region that his opponents had argued could not be won by a long-term Bay State politician.

"Once again, the message rings out loud and clear. Americans are voting for change – East, West, North – and today in the South. Thank you, Tennessee; thank you, Virginia.," the Massachusetts senator said in a victory speech to voters in Northern Virginia. "You showed that the mainstream values we share – fairness, love of country, a belief in hope and hard work – are more important than boundaries or birthplace."

Beginning to recognize his place as the presumptive nominee, Kerry spoke on an issue that has crept into the general election debate so far – President Bush's military service with the National Guard (search). 

Kerry said Tuesday night that he doesn't want to hear his surrogates questioning whether Bush fulfilled his National Guard service, which Democratic National Committee (search) chief Terry McAuliffe first questioned less than two weeks ago.

"It's not an issue to me and I have never made an issue in the course of my entire career about what choices anybody made about where they served, or didn't serve," Kerry told Fox News.

Though he has not previously suggested his opponents should step aside, Kerry also suggested that candidates who have not "grown" from the race should perhaps bail from it.

"I think the whole campaign has made me a better candidate. I am sure it has made [my opponents] better candidates too. I think those who don't grow and learn in this process should get out of it," he said.

On Tuesday night, John Edwards (search) placed a distant second in Tennessee and Virginia despite being the U.S. senator from Virginia's southern neighbor, North Carolina. Wesley Clark (search), who hails from Tennessee's neighboring Arkansas, finished third there as well as in Virginia. Both candidates had argued that they would win big in their regions, predictions that not only were overzealous, but perhaps set up expectations that are fatal to their campaigns.

Clark appeared to feel the wound on Tuesday, announcing late in the night that the retired general was headed back to Little Rock, and would announce Wednesday that he was stepping out of the race.

"The results tell us that Wes Clark, who was campaigning most heavily and wanted to win Tennessee did not only not win, but he finished third," Roll Call Executive Editor Mort Kondracke said before Clark's announcement. "That removes more rationale from his candidacy. Who's going to give him any money now?"

Aides, who already have not been paid for more than a week, said that Clark lacks the cash to advertise aggressively and would have had to camp out in Wisconsin for lack of travel money.

Clark made it clear before he entered the race that part of his lengthy deliberation about running or not was concern about his personal finances, and sources said his family was not enthusiastic about going into debt for a losing endeavor. Senior staff added that they can't afford to continue to travel around the country for a man who cannot win the nomination.

Prior to the announcement about dropping out, aides said Clark had spoken with Kerry after Tuesday's primaries and appeared to suggest that his concession would go beyond Tennessee and Virginia.

Edwards said that he would keep on fighting through Wisconsin next Tuesday and possibly into March 2, known as Super Tuesday (search) because of the large number of delegates to be pledged that day. But sources said Democratic operatives have urged Edwards to consider dropping out of the race in order to give Kerry the room he needs to collect donations and launch a general campaign.

Speaking to supporters in Wisconsin, Edwards gave no hint of backing down. 

"Thank all of you – all of you – the voters who voted today in the election, for saying to the country that we're going to have a campaign and an election, not a coronation," Edwards said. 

Sources close to the campaigns say both Edwards and Kerry staffers immediately began seeking Clark supporters.

Howard Dean (search), who decided to skip the southern states and concentrate on Wisconsin, placed a distant fourth in both states. Rallying supporters at a church in Milwaukee on Tuesday, Dean said that the Wisconsin primary is a big deal – it is a chance to turn around a campaign that has been managed and damaged by the media and pollsters.

The two wins in Tennessee and Virginia were fail-safes for Kerry's ascendance to the Democratic presidential nomination, say many observers, who noted that a large part of the support for Kerry comes from his electability. In exit polling, among those who voted for Kerry in Virginia, 77 percent of them said that their most important issue was the candidate's ability to beat Bush.

"Kerry has run steady, it has been a very sound campaign. [Democrats] united on the fact about beating George Bush. They hate Bush more than they loved Dean or anyone else and that's the rationale for the campaign," said Empower America chief Bill Bennett.

As he reaches for the nomination, Kerry's support is growing exponentially. He has the backing of 47 U.S. House representatives. On Wednesday, the Alliance for Economic Justice (search), a coalition of 21 industrial unions including the Teamsters, United Steelworkers of America, International Association of Machinists and Aerospace Workers, International Association of Iron Workers and the Laborers' International Union of North America, is expected to conduct a private conference call of its executive boards and unanimously vote to endorse for Kerry.

The accelerated primary schedule created by McAuliffe was meant to help the front-runner by consolidating support and helping him gain money against the well-funded Bush. Some observers say it has succeeded.

"The Bush haters now have mobilized nationwide. The Bush haters are up and running and they are ready to go. They are loaded for [a fight] and Howard Dean has gotten that going," said radio talk show host Laura Ingraham.

But some analysts warn that with a long general election ahead of him, Kerry has a tough struggle. Because it has been only four weeks since the Iowa primary, that means the Vietnam vet still has almost nine months until the general election.

"The Republicans haven't taken the field yet, have they? The offense hasn't come on the field, so we'll see," Bennett said. "It's no doubt that it's Kerry's legislative record, his public service, not his military service that will be at issue, and there's a lot to answer for."

"John Kerry's moment under the microscope has not really begun yet," said Fox News radio host Tony Snow. "This is a guy who has plenty of enemies within his own party, let alone on the Republican side. But, you know what, this is the Democratic primary season, he can sow his oats right now."

Fox News' Carl Cameron and Sharon Kehnemui contributed to this report.