Vice President Gore accepted the resignation of campaign chairman Tony Coelho today, summoning Commerce Secretary and long-time Democratic strategist William Daley to take over stewardship of his presidential campaign.

Coelho, who suffers from epilepsy and was hospitalized this week with an inflamed colon, called Gore from his hospital bed late Wednesday night to say he had to step down for health reasons.

This marks the second major staff change on a Gore team that has for months experienced internal disharmony and struggled to find a consistent message. In tapping Daley, Gore chose a seasoned operative who first learned politics from his late father, Chicago Mayor Richard J. Daley, and applied those skills to help elect his brother, Richard M. Daley, to the same job and Bill Clinton to the White House in 1992.

"I am thrilled that he has agreed to take over as chairman of the campaign, to relocate to Nashville and spend full time as a hands-on chairman of the campaign," a beaming Gore said during a news conference here. "He will have complete charge of the campaign. Everybody on the team is excited about that, most of all me."

Gore praised Coelho for doing "a terrific job" and credited him for the campaign's success in the primaries. Then he reassured supporters: "We're not going to miss a beat."

Coelho, 58, has been a controversial figure who quickly made his mark on the campaign by ousting several high-paid Gore loyalists. He is also being investigated by the State Department for some of his activities when he ran the 1998 World Exposition in Portugal. Today, Gore stressed that Coelho's health was the sole reason for the change.

From his hotel in Manhattan on Wednesday night, Gore conferred with his wife and brother-in-law and telephoned Daley around midnight. Neither consulted with President Clinton before sealing the deal. "I took his commerce secretary away before I told him," Gore said explaining that he called the president today in between campaign stops in Ohio.

Daley said he plans to fly to Nashville after weekend meetings in Washington with Gore. White House sources said his deputy, Robert Mallett, will likely replace him when he officially steps down July 15. Gore also said he removed Daley from consideration for the No. 2 spot on the Democratic ticket since it would be impossible to do both jobs.

Gore's late-night call caught Daley by surprise. As recently as Tuesday, Daley insisted there was nothing to persistent rumors that he was going to assume the chairmanship from Coelho and said at the time that no one from the campaign had approached him about coming in.

In a telephone interview, Daley acknowledged that George W. Bush has had three good months since the end of competition in the Republican primaries. "I'm not diminishing the ability of Bush to move away from his stridency and what he did to McCain in the primaries," he said. "He's been pretty deft."

Daley said Gore's new focus on the economy showed that the vice president now has "a good game plan" in place, and the immediate challenge is to keep the contest close between now and Labor Day. "If we're in a dead heat after Labor Day, we're in a horse race and this is going to be a close race all the way," he said. "That's a good position to be in."

For more than a year, Gore has had his eye on Daley and acknowledged today he came close to offering him the job before Coelho.

Friends said Daley, 51, is a more even-tempered leader than Coelho and comes free of controversy. Because of past and current ethics investigations, Coelho rarely spoke in public, leaving Gore without a prominent spokesman. Without those liabilities, Daley is expected to play a higher public role than his predecessor. "Where he has the real advantage over Tony is to be able to act as a surrogate and go on the Sunday talk shows," said one congressional Democrat who knows both men. "In that sense, Daley brings more to the table."

After running the Democratic National Convention in Chicago in 1996, Daley came to Washington to replace the late Ron Brown as commerce secretary. Earlier, he had been summoned by Clinton to lead the effort to win passage of the North American Free Trade Agreement in 1993. As secretary this year, he helped gain approval of a pact granting permanent trade status to China.

AFL-CIO President John Sweeney, while praising Daley as a man with "proven ability," nevertheless expressed concern about his role in those two votes. "Unfortunately, his leadership of the president's campaigns for NAFTA and PNTR with China put him squarely on the opposite side of working families," Sweeney said. "In his new position, he needs to prove he can fight just as hard for American workers as for those trade deals."

Gore told reporters aboard Air Force Two that Sweeney was the first person he telephoned this morning and that he plans to meet with the labor leader in the next few days.

One source close to the House Democratic leadership said Daley brings good managerial skills to the campaign that are needed in an operation where "there are already too many strategists," citing consultants Carter Eskew, Robert Shrum and Harrison Hickman.

"He brings a sense of confidence, leadership; people enjoy working with him," said Rahm Emanuel, a Chicago Democrat and former White House adviser.

Coelho's year-long tenure as the campaign's unpaid chairman has been marked by a succession of achievements and bitter turf battles. He is largely credited with overseeing the move to Nashville and slashing spending during the critical months when Bill Bradley posed a serious primary threat to Gore.

"Love him or hate him, you've got to give him credit for what he did in the primaries," said Tom Nides, a longtime Coelho ally. "The good news is he is leaving at a time when people perceive the campaign to be in good shape. They are dead even in the polls, there's money in the bank, they've got a good message and a good staff."

An epileptic known for his frenetic pace and long hours, Coelho said today that the strain of the job triggered three seizures this year, compared with his standard one every five years. "This would have been a tougher decision for me had I not felt I completed my job of making the necessary changes," he said in a telephone interview. He noted the irony of today's date: Precisely 26 years ago he was diagnosed with epilepsy.

Staff writers Dan Balz and Thomas B. Edsall in Washington contributed to this report.