Philadelphia's small but vocal band of self-styled reformers was jubilant last week, dancing a figurative tattoo on the corpse of the old politics.

Bloggers, "goo-goo" (good government) organizations, and Generation X Democratic activists weaned on the 2004 Howard Dean presidential campaign all claimed some credit for City Councilman Jim Kenney's sudden withdrawal of legislation to gut the campaign-contribution limits that the city enacted four years ago.

Kenney's Tuesday night about-face emboldened the activists as they seek to influence the mayoral race that's unfolding. It remains a matter of debate among political strategists, however, whether that new energy means municipal corruption and political reform will emerge as driving issues in the May 15 Democratic primary.

In January's Keystone Poll, two-thirds of Philadelphia voters said crime, not political reform or anything else, was the issue. Most analysts believe reform questions will influence the margins of the race at best, but activists believe anger is rising in Philadelphia, as it did across the state last year after the legislature gave itself a pay raise.

"I think we're breaking through, people are waking up," said Anne Dicker, a founder of the liberal group Philly for Change and a leader in the movement against two proposed casinos. "People in Philadelphia want change," she said, a desire that "cuts across a lot of lines."

The shifting legal and political terrain around the city's caps on campaign giving has already forced four of the mayoral campaigns to adjust tactics and strategy several times.

First, they had to raise cash under the limits of $5,000 from an individual donor and $20,000 from a political committee. Then came Kenney's first proposal, to eliminate those caps, followed by his second, to have floating caps.

Even with Kenney having backed down, the hard limits might not last: A pending lawsuit scheduled for a hearing March 7 in Commonwealth Court could result in judges' striking down the city's campaign-donation caps as a violation of the state constitution.

Millionaire Tom Knox, who has already loaned his own campaign $5 million and vows to spend "whatever it takes" to win the mayor's office, is the cause of much of the uncertainty. Knox sent a jolt through the race with a $2 million TV ad blitz that rocketed him to second place in a January poll.

Kenney argued that it was unfair for other candidates to have to abide by caps when a rich person could spend without limits. The move was widely derided as an assist to the candidate Kenney supports, U.S. Rep. Bob Brady, who entered the race late.

The councilman withdrew his proposal after it was blasted by a chorus of activists, media commentators, and, most important, challengers for Council seats in the May 15 primary.

"That made the political impact of voting for this very clear to Council members: 'Why should I give them a stick to beat me with?' " said a veteran Democratic campaign consultant, Howard Cain. "It's all about political survival."

If courts kill the limits, Brady and U.S. Rep. Chaka Fattah could gain, strategists for various campaigns say. Brady has deep labor support, and unions could pour money into his fund. State Rep. Dwight Evans also has some unions, such as the United Food and Commercial Workers, in his corner.

Fattah financed an exploratory committee with donations from a handful of the rich and super-rich; some say Fattah could get quick aid from them.

With the limits in place, Brady gambled last week by committing $281,250, more than half the amount he had on hand as of Dec. 31, to a TV ad campaign meant to catch up with Knox. Fattah has concentrated on building a voter-turnout organization while counting on media coverage of his policy proposals for exposure.

Evans plans to debut his first television commercials this week. But he's also been experimenting with new and less expensive ways to engage voters.

On Tuesday, Evans staged a live, 47-minute Webcast in which he replied to e-mailed questions. His campaign said 290 people went online to watch at least part of the event. Another is scheduled for Wednesday.

"It's almost like an electronic kaffeeklatsch," Evans said. "It's a lot cheaper than TV, and it gives people a chance to talk to me."

Evans said some regular political donors like the limits: Candidates can't keep coming back to them for more. He added, "If the court throws [the limits] out, that really throws things up in the air."

The case stems from a lawsuit filed last spring by another mayoral hopeful, former Councilman Michael A. Nutter. He claimed his potential rivals were violating the city's ordinance by accepting money in excess of the limits while acting like mayoral candidates, even though they had not declared themselves such.

Nutter withdrew his complaint after he declared his own mayoral candidacy. Labor leader John Dougherty filed a counterclaim, arguing that the city has no right to regulate campaign cash under the state constitution. It's not clear what will become of Dougherty's claim now that he has decided not to enter the mayor's race.

To make sure the case stayed alive, Fattah intervened in the suit in December, taking up Dougherty's argument. A judge initially ruled that only the state can regulate campaign cash. The city and Nutter appealed.

Now, Fattah's role in keeping the suit alive could have the effect of blowing up the campaign caps, which were among the few concrete changes enacted after the "pay-to-play" scandal that rocked City Hall in 2003.

Fattah said he's standing firm because Nutter's original suit implied he was acting improperly. "There's never been a blemish on my good name, so I'm going to see that this is clarified," Fattah said last week.

He also said he would consider dropping the case if Knox agreed to a "reasonable cap" on spending his personal fortune. Knox has scoffed at this idea.

The caps - along with curbs on giving by firms that want no-bid city contracts - have slowed the money flowing into the mayoral race. Many law firms, for instance, are wary of raising money for candidates.

The rules for contract-seekers, another product of the pay-to-play scandal, would likely stay in place even if the donation limits are struck down, legal experts say.

But if the caps survive the court challenge, the non-millionaire mayoral candidates will have to make do with less.

"It becomes a question of guns or butter for campaigns: Do we put the money on TV or on the street?" said Democratic consultant Larry Ceisler, who is not involved in the contest. "They may have to make some tough choices."

For continuing coverage of the mayor's race, including profiles of the candidates, go to http://go.philly.com/mayorEndText

Contact staff writer Thomas Fitzgerald at 215-854-2718 or tfitzgerald@phillynews.com.

Inquirer staff writers Larry Eichel and Marcia Gelbart contributed to this article.