Updated

After weeks of backroom dealing, Democratic presidential candidate Howard Dean formally received on Wednesday two big labor endorsements that everyone knew were coming but still helped cement the former Vermont governor's front-runner status.

The presidents of the American Federation of State, County and Municipal Employees (search) and the Service Employees International Union (search), largely made up of health care workers inclined to back a physician candidate, announced their joint backing in a carnival-like atmosphere that included hundreds of flag-waving, cheering union members.

"After November, there will be a doctor in the house — the White House," said SEIU president Andy Stern.

The AFSCME, comprised of government workers, had toyed with the idea of backing Missouri Rep. Dick Gephardt, supported by 21 other unions, then Massachusetts Sen. John Kerry and retired Gen. Wesley Clark. In the end, the union joined its sizable rival in concluding that Dean is the most electable opponent to President Bush.

"This man of Vermont has the best chance to beat Bush," said Gerald McEntee, president of AFSCME. "As governor, he made the tough choices necessary to move that state forward. He will do no less for our country."

But Dean still lacks support from many Democratic Party leaders and activists who question his temperament and worry that liberal aspects of his record will be easy targets for Bush. The fear is that he will follow in the footsteps of White House losers Michael Dukakis in 1988 and Walter Mondale in 1984.

McEntee, who was instrumental in the nomination of Bill Clinton in 1992, acknowledged the concerns of many, and said, "I had to make a lot of very tough phone calls over the course of the past week."

The two unions represent about 3 million workers nationwide and are among the only labor organizations that are actually growing. Both are active and influential forces in the early voting states of Iowa and New Hampshire, and promise Dean will receive big organizational and financial help.

AFSCME, for instance, spends more on politics than any other union. In the 2000 cycle, the union spent $40 million, said political director Larry Scanlon. The unions promised that they will help Dean, who has successfully used the Internet to outpace his rivals in fund raising, to reach his goal of getting 2 million supporters to contribute $100 each as he foregoes taxpayer money and accompanying spending limits to take on cash-rich Bush.

The unions' decisions to back Dean came as a crushing blow to Gephardt, who had hoped but now has lost any chance of winning the biggest labor nod from the AFL-CIO, the national umbrella group for 13 million labor unionists.

Gephardt was well on his way to the two-thirds threshold of support from member unions of the AFL-CIO. That's the number needed for an overall AFL-CIO endorsement. Without the SEIU, the blanket nod is out of reach, leaving Dean triumphant.

"This is an extraordinary thing that you've done over the last week. It will change America because it will put working people back in the driver's seat," said Dean, who was wearing a green AFSCME T-shirt and purple SEIU jacket.

But Gephardt is still going strong in Iowa, where one in three caucus attendees comes from a union household. Gephardt recently pulled ahead of Dean in polls there. He also has the support of the state's United Auto Workers, with about 18,000 members and the Teamsters and United Food and Commercial Workers, each with about 15,000 members. The AFSCME has about 13,000 members in Iowa. The state branch of the National Education Association (search), with about 30,000 members, is still neutral.

Veteran activist Phil Roeder said AFSCME and SEIU are the "best two field organizing unions" in the state.

"Gephardt probably still has the upper hand, but Dean certainly made a big jump in his direction," said Roeder, who supports Kerry.

By winning the double-barreled labor nod, Dean also hopes to broaden his campaign beyond what critics say amounts to a single-issue candidacy based on his opposition to the Iraq war.

Clark Calls on Saudi Help in War on Terror

Meanwhile in New Hampshire, Clark, who joined the race ostensibly as a single-issue war critic, albeit with a distinguished military record, took a swipe at both rivals and critics who have not served.

"The difference between me and chicken hawks is I've been there," Clark told an audience at Dartmouth College. "This is not about public policy pronouncements ... or writing policy papers ... It's all about leadership with me. I'm not just someone who can talk the talk, I've walked the walk."

Clark and Kerry are the only two presidential candidates who have seen military action. The rest, including Bush, never served or never saw combat as members of the National Guard.

Clark unveiled his plan to catch Usama bin Laden by shifting some U.S. forces back to Afghanistan from Iraq, improving relations in the region and involving the Saudis in a commando search of the Afghan-Pakistani mountains where bin Laden is believed to be hiding.

Clark said that since many of the leaders of Al Qaeda come from Saudi Arabia and many of the attacks are aimed at targets in Saudi Arabia, the country has a vested interest in stepping up cooperation with the United States in capturing bin Laden.

"It's time for real action from the Saudis to help take down Al Qaeda," he said. "What we haven't done is use our leverage and connections with the Saudis to in turn leverage their connections in the region effectively."

Clark's rivals call him naive for thinking the Saudis, who have been criticized for dragging their feet in the war on terror, would join the fight beyond their own borders. He said it could be done.

"Of course this would be developed in consultation with both countries," he said. "It probably would be a compartmented program you wouldn't discuss publicly — you'd talk about it when the results came through."

Fox News' Carl Cameron and The Associated Press contributed to this report.