When the big dog jumped in the pool last week, some water sloshed onto the deck, but the rest of the dogs kept paddling.

Former City Councilman Michael A. Nutter was suing gun sellers, U.S. Rep. Chaka Fattah unveiled a health-care program, State Rep. Dwight Evans met with crime victims - and millionaire businessman Tom Knox's commercials continued to run without rebuttal on local TV stations.

U.S. Rep. Bob Brady, the big dog by virtue of his 20 years as boss of the city Democratic machine, no doubt changes the equation in the Philadelphia mayoral primary race he officially joined on Thursday. Still, political strategists and analysts say each of the five candidates has a plausible chance to win May 15.

In other words, it's a real race.

"There's enough fluidity that anything can happen," said Terry Madonna, a professor at Franklin and Marshall College and director of the Keystone Poll, who has polled city voters for more than 15 years.

Over the last three decades, open Philadelphia mayoral elections (with no incumbent running) have often come down to the racial divide, with the winners showing an ability to strike deals that expand support just a little beyond their ethnic bases.

While coalition-building will be important, there are some signs this time that the electorate may be less polarized along racial lines than in the past. Two African Americans - Nutter and Fattah - ran first and second among white voters in one recent poll. A white candidate, Brady, by getting elected and reelected to Congress from a "majority-minority" district where most voters are African American, also has demonstrated cross-racial appeal.

And this year, the Philadelphia electorate - all races - appears united on one thing: Change is needed.

In recent polls, no more than 30 percent of respondents have said the city is headed in the "right direction." By contrast, about half of Philadelphians four years ago felt things were on the right track, and two-thirds were bullish in 1999, in the last days of the Rendell administration.

The new "wrong track" majority, analysts say, may be good news for voters sick of spin and counterspin and negative campaigning: It puts a premium on candidates who offer substance, and on the projection of leadership qualities.

"When the 'right-track/wrong-track' numbers are as bad as they are, people are looking for more than 'This guy is from my neighborhood,' " said Democratic consultant Dan Fee, who worked for Gov. Rendell's campaigns but is not working in this race.

"People are looking for candidates who can deliver a vision on the issues," Fee said last week. "Who is going to rise above the base and be the whole city's candidate?"

Here is a political snapshot of the race at this point, based on interviews with a dozen strategists and analysts:

Chaka Fattah

Strengths.

The front-runner in polls, with high name recognition and a strong identification with educational issues. Though an officeholder at state and federal levels for 25 years, Fattah has been aloof from the Democratic machine and thus is in the enviable position of being both an outsider - at a time voters want change - and an insider. He has his own strong political operation, and has been churning out detailed policy proposals.

Weaknesses. Strategists for rival camps believe Fattah may have a glass jaw, pointing to his irritation at gibes about his educational background and work ethic. Some of these were cheap shots, they say, but in politics it doesn't pay to let your annoyance show. Also, some of Fattah's votes in Congress could be construed by foes to suggest he's "soft on crime." Every other candidate has an incentive to tear down the leader.

Path to victory. Keep pushing a positive vision of an "opportunity culture," increase his fund-raising, and hang around to emerge as the electable alternative to Brady, scooping up the white Center City liberals now attracted to Nutter. "It's still Chaka's to lose," said veteran Democratic operative Maurice Floyd. Privately, key Brady backers agree.

Bob Brady

Strengths.

The Democratic machine is creakier than it used to be, but Brady's rivals would salivate to have the support of most of the leaders of the city's 69 Democratic wards, as he does. He also has a regular-guy, blue-collar history that may appeal to the archetypal white "rowhouse" voter once attracted to Mayor Frank L. Rizzo - without Rizzo's polarizing aspects. Brady, a large and avuncular man, also projects confidence and strength. He has a well-honed reputation as a peacemaker in labor disputes.

Weaknesses. Brady has not been known for his fluency in public policy, and some question whether he can get the "vision thing" down. He will try to turn this into a strength, as he did at his announcement, arguing that sheer leadership is more important than what he called "25-point plans." As longtime city Democratic boss, Brady also symbolizes the status quo at a time voters appear to want change.

Path to victory. Deflate Knox, the other white candidate; use his own ward-level ties and constituents' goodwill to attract a share of black votes to go with his natural base in South Philadelphia, the river wards and the Northeast. Turn his insider-ness into a plus by arguing that outsiders are ineffectual - "Jimmy Carter can't get it done," as a Brady strategist put it.

Michael A. Nutter

Strengths.

Has shown wide appeal across racial lines. As the champion of the city's new government-ethics ordinance and campaign-finance limits, he is well-positioned as a "reform" candidate. "If you were basing it on which candidate is the brightest, you'd have to give the edge to Michael Nutter," Democratic strategist Frank Keel said. "He's a wonk's wonk."

Weaknesses. As a former district councilman, Nutter has a small geographic base in West Philadelphia. His weaker polling among blacks could be a problem, which may be one reason Nutter called himself an "outraged black man" in announcing his anticrime package on Jan. 16.

Path to victory. Increase his share of the black vote.

Tom Knox

Strengths.

Self-financed and has tons of money. He already has spent more than $2 million on TV ads that have been running for about six weeks. He has had the airwaves to himself. Insiders expect Knox will show up in second place in the Keystone Poll due to come out next week. He has a compelling personal story of rising from public housing to astronomical business success. Knox also is an outsider who can argue that he can't be bought. He served in the administration of the city's last super-popular mayor, Rendell.

Weaknesses. He's an outsider, with no natural constituency. Knox, whose hobbies include fine dining and wine-sipping, can be portrayed as out of touch with average voters. He made some of his money with payday loans, and his opponents are sure to attack him as a predator. Knox also tends to be a wooden campaigner. "He's moved the needle well with his media blitz, but . . . I would keep him under wraps," Keel said.

Path to victory. Bludgeon everybody else with advertising. If videos of the candidate windsurfing exist, destroy them.

Dwight Evans

Strengths.

Has united several warring factions among the city's black politicos, has an impressive record of spurring redevelopment of his West Oak Lane neighborhood, and is a power in Harrisburg, with an ability as House Appropriations Committee chairman to continue bringing money back to the city. (His campaign slogan is "Block by block.") Evans also has an extensive record of working on this year's red-hot issue: strategies to fight crime.

Weaknesses. His base in Northwest Philadelphia is small, and many voters in the rest of the city are not aware of his behind-the-scenes work over the years on crime and education.

Path to victory. Take aim at Fattah to knock down his numbers. Launch a vibrant advertising campaign to tell his West Oak Lane story.

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

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