President Clinton, whose capacity for helping or hurting the campaigns of his wife, Vice President Gore and other Democrats is much debated in political circles, conceded today that his powers are limited as an endorser and surrogate speaker.

The president, in Philadelphia to help an embattled mayoral nominee, opened his speech with an anecdote about how fruitless such appearances can be for any president. He told a crowd of several hundred at LaSalle University that when he ran for Arkansas governor in 1984, a popular president, Ronald Reagan, came to campaign for his opponent.

"Then [Reagan] got 62 percent in the election, and so did I," Clinton said. "And it made me always a little apprehensive." He said he came today "not as president to tell you how to vote," but as "a good friend to Philadelphia to talk about why."

His appearance here, on behalf of mayoral candidate John F. Street, was the latest example of Clinton's sometimes wistful acknowledgments that the political spotlight is turning inexorably from him. Even Gore, whom he praises in virtually every speech, has publicly questioned whether he wants Clinton's help in the 2000 presidential race, and New York Democrats are divided on how much he can help Hillary Rodham Clinton in her Senate bid.

"You know, I'm not running for anything anymore," the president told today's audience, which included many labor union activists and African American students who cheered him loudly. "I kind of hate it, but I'm not."

Clinton's relationship with Democratic candidates has been uneven. On one hand, he has raised money relentlessly for the party and often gives inspired speeches to party activists. But he angered congressional Democrats in his first term with talk of "triangulation," or distancing himself from their policies. Just as those relations were healing, his second-term sex scandal and impeachment ordeal damaged his appeal as a surrogate campaigner.

Last month, Clinton stumped in New Orleans for Democratic gubernatorial candidate William J. Jefferson, who was trailing badly in the polls. Republican Gov. Mike Foster easily won reelection in that race.

Clinton's greatest strength, perhaps, is not in persuading on-the-fence voters but in energizing the party's core constituencies shortly before an election. That was the hope today in Philadelphia, where Street is locked in a tight race with Republican Sam Katz even though registered Democrats outnumber Republicans about 4 to 1. Street, a former city council member, has run a haphazard campaign, local activists say, and Philadelphians may be ready to elect their first GOP mayor in half a century.

The president acknowledged the concerns, saying he had read that Street "was a very good man, but he didn't have any vision, and he wasn't very charismatic." He said Street's thundering speech, which preceded Clinton's, disproved such criticism. Giving Street partial credit for Philadelphia's improving economy and falling crime rate, Clinton cited the neck-and-neck race and asked, "What is the deal here?"

Also speaking for Street were Sen. Edward M. Kennedy (D-Mass.) and Philadelphia Mayor Edward G. Rendell, who called Street the city's "best-qualified" mayoral candidate ever.

White House officials had said Clinton would devote part of his speech to the ongoing budget battle with Congress, but the president mentioned it only briefly. He said he had agreed to another week-long interim spending measure "because Congress still can't pass a budget because they can't figure out what to do. They want you to believe they're for certain things, but they don't want to pay the price for being for them."

After a $300,000 Democratic Party fund-raiser in Atlanta, Clinton addressed the Anti-Defamation League, where he criticized Congress for failing to fund U.S. obligations under the Wye Plantation Mideast peace accords as part of the State Department appropriations bill. "That bill sent a terrible signal to our friends in the Middle East," Clinton said. "I'll veto it again if it doesn't provide for the funding of our obligations around the world."

He also called on Congress to pass legislation broadening federal sanctions against hate crimes. Clinton said that if he could give America just one gift, it would be "the ability to be one America . . . to revel in our diversity."