Armed with 96 percent of the Democratic primary vote, Pittsburgh Mayor Luke Ravenstahl comes to work today fortified by that strong showing at the polls.

But stripped of three council allies and facing an ambitious new controller, the mayor faces more uncertainty than at any time since his Sept. 1 ascent to office.

That's the situation wrought by Tuesday's election, which took a city government already seasick from 17 months of nonstop mayoral transition and handed it some syrup of ipecac. While the mayor sailed to unopposed victory, voters chose newcomers to city government for four of the city's elected offices.

"It was kind of a primary pot luck," said state Sen. Jim Ferlo, a former councilman.

"The perfect storm of reform" is how Councilman William Peduto saw it.

Preliminary Democratic primary results showed challengers Bruce Kraus, Patrick Dowd and Ricky Burgess beating, respectively, incumbents Jeff Koch, Len Bodack and Twanda Carlisle. Allegheny County Prothonotary Michael Lamb won the city controller nomination.

"I don't necessarily think that is going to affect my agenda," Mr. Ravenstahl said of the coming changes, listing fiscal prudence and development as priorities.

The high turnover, though, has no precedent in the two decades since at-large council elections were replaced with by-district voting, observers agreed.

"It's something we haven't seen happen as long as I can remember, and I've been watching city politics for 30 years," said Councilman Jim Motznik.

Observers don't agree on why it happened.

Mr. Ferlo said voter apathy allowed spirited challengers to win the day. In addition, Ms. Carlisle faces criminal corruption charges. "I think this is all progressive and good," he said.

Mr. Peduto argued that the results represent "the transformation of Democratic politics" by a new infrastructure of progressive groups, campaign workers and candidates. Two of the ousted incumbents were endorsed by the Democratic Committee and the Allegheny County Labor Council, suggesting traditional power bases can't guarantee victory.

"If there's a significant amount of negative publicity, that can trump the endorsement," said city Democratic Committee Chair Barbara Ernsberger. Mr. Koch, she noted, was swamped with stories about campaign irregularities in the race's final week.

Anti-incumbent sentiment in a city still losing population and struggling fiscally could also play a role, said Morton Coleman, former director of the University of Pittsburgh's Institute of Politics and an executive of city government in the 1960s.

If that sentiment holds, it could prove troubling to Mr. Ravenstahl, who may face Republican Mark DeSantis in November's General Election, and would face primary voters yet again in 2009.

Republicans held a write-in drive for Mr. DeSantis, a Downtown businessman. The Elections Division reported 1,408 Republican mayoral write-in votes, but it may not be known for two weeks whether Mr. DeSantis got the necessary 250 votes and bested all other write-in candidates.

"I'm optimistic," Mr. DeSantis said. "I'm meeting people who are interested in a campaign."

"If we have a Republican opponent, my focus will still be governing and doing the right things," Mr. Ravenstahl said.

He would be a heavy favorite, but even if he wins big, he might find governing tougher in 2008.

That's because a council that -- with the exception of Mr. Peduto -- has been mayor-friendly will get three independent voices. Mr. Kraus, particularly, has no debt to Mr. Ravenstahl, since mayoral pal and Redd Up Campaign Manager Kevin Quigley was campaigning for Mr. Koch on Tuesday.

"It's no longer an 8-1 council for Luke," said Mr. Peduto, who backed Mr. Kraus and Mr. Dowd in prior races and abandoned a mayoral challenge in March.

Mr. Ravenstahl said he looks forward to working with the new council members. "I certainly don't have the same close working relationship with them that I do with the three individuals that will be leaving," he added.

He's also pledging to work closely with Mr. Lamb, who ran for mayor in 2005, but yesterday disavowed a 2009 bid.

"I have no intention of running for mayor in two years," Mr. Lamb said. "I can have the impact I want to have on this city from the position of controller. ... I'm hoping that the relationship [between his office and the mayor's] will be one of trust, and one that will work toward the same end, which is the betterment of the city of Pittsburgh,"

Mr. Lamb said he'll get involved as early as this summer in lobbying the General Assembly for solutions to pension funding, a problem the city shares with many other municipalities.

Though that's also a priority of Mr. Ravenstahl's, the mayor claimed not to feel encroached upon.

"Michael and I have always had a good professional, working relationship," the mayor said. "To hear his agenda of being aggressive and lobbying on the city's behalf in Harrisburg is good news."

Can everybody really get along? "There will be people with new ideas," said Ms. Ernsberger, "and we'll see how it all works out."