Four years ago, then-President Bill Clinton spent much of the fall campaign season stewing in the Oval Office -- largely banished from the trail on orders from the Democratic nominee.

This year, Clinton will spend at least a portion of the next eight weeks stewing from his hospital bed and living room. The difference is that this year, other Democrats are as frustrated at having Clinton on the sidelines as he is to be there.

Clinton's heart surgery yesterday means that he will miss most or all of political trips and Democratic fundraisers in September. The former president hopes he will have recuperated sufficiently to resume a political schedule by October, including appearances on behalf of Democratic nominee John F. Kerry, but his aides and political handlers said this remains uncertain pending doctor's orders.

"He's eager to help," said Washington lobbyist Steve Ricchetti, a former White House deputy chief of staff who still handles much of Clinton's political business. "It will be absolutely dependent on what the doctors say he can and should be doing."

In the days before physicians surprised Clinton by informing him that he had severe blockage of his coronary arteries -- prompting urgent heart bypass surgery at a New York hospital -- he had been firming up his political schedule for the next several weeks. Ricchetti said Clinton had committed, or was on the verge of committing, to about eight major fundraisers.

These included events for the Democratic National Committee and the two political arms of congressional Democrats -- the Democratic Senatorial Campaign Committee and the Democratic Congressional Campaign Committee -- advisers said.

In addition, Clinton will cancel a planned trip to Asia to promote his memoir, "My Life," and will postpone an energy forum sponsored by his foundation, which had been scheduled for later this month.

Charles Cook, an independent political analyst, called Clinton's temporary sidelining unwelcome news for Democrats, including Kerry. The fundraisers, he said, "would be hard to replicate, and even if they get pushed back until October that's later" than candidates would like to see the money.

On the other hand, some commentators noted that Clinton's illness means that, when he does return to the trail, the event will be invested with an element of attention-getting drama and sympathy that it would not have otherwise.

For the all the hoopla that surrounds Clinton's personality -- underscored by a headline-grabbing appearance at the Democratic National Convention in Boston in July -- his political impact should not be exaggerated, Cook cautioned, particularly when it comes to Kerry's fortunes. "He wasn't going to be a big hit with swing voters," the analyst said, noting that Clinton's use for Democrats is principally as a draw to raise money, and also to excite core Democrats to turn out to the polls.

This year, polls suggest that these Democratic base voters are already highly motivated to turn out because of their disdain for President Bush.

Even so, the contrast with four years ago is notable. Then, Vice President Al Gore, running for president, and his strategists believed that "Clinton fatigue" -- motivated by disgust with Clinton's personal behavior with Monica S. Lewinsky and his subsequent deceptions about it -- was a significant liability with voters, particularly culturally conservative independents in crucial states such as Ohio. The question of how Gore would deal with Clinton became a major subtext for the campaign.

Only at the end of the 2000 campaign did Clinton hit the road on Gore's behalf, and even then not in states that were in close contention. After Gore narrowly lost the election, there was ample second-guessing among Democrats about whether he had erred in not putting Clinton and the administration's economic policy record to better use.

This year, Kerry has avoided this mini-drama by stating that he is eager to use Clinton on his behalf. What exactly this means, however, has not been spelled out by Kerry aides. They maintain that it has not been decided, and won't be until later in the season, as strategists judge which states and which voters remain up for grabs, and what kind of appeal would work for them.

Clinton had kept large chunks of his schedule open. Ricchetti said he had been discussing the matter with Kerry campaign manager Mary Beth Cahill and others.

"There certainly was every expression of a desire to have him be helpful, his schedule permitting," he said.

Now Clinton's heart must also be permitting. Although bypass surgery is deeply invasive, it allows far faster recovery times than it did years ago. But returning to a sedentary desk job is not the same as hitting several cities a day and staying up late at dinners and receptions -- the normal pace of a politician in campaign mode.

Ramin Oskoui, a cardiologist at Washington Hospital Center, said patients should expect to spend four to seven days in the hospital after the surgery, and then about four weeks in convalescence before going back to work.

"If common sense prevails rather than ego, you will stay in six weeks," Oskoui said. "That is a factor with a lot of high-powered individuals -- they push to go back to work."

Staff writer Shankar Vedantam contributed to this report.