Amy Stoddard left South Side's Market House Tuesday evening without voting for Pittsburgh mayor.

Incumbent Luke Ravenstahl, a Democrat who also won the Republican nomination, is "kind of irresponsible," the graduate student said. Independents Franco Dok Harris and Kevin Acklin didn't excite her. "When you have two guys running against one who's already in, [the incumbent] is going to win," she said.

So she joined 1,255 other city voters in choosing no one for mayor. Mr. Ravenstahl won her ward with a tepid 53 percent of the vote -- 5 percentage points below his share there in a 2007 special election.

That showing, and Ms. Stoddard's ambivalence, roughly mirrored voting citywide. The mayor got 55 percent of a low-turnout vote versus the 63 percent he won in 2007. Yesterday, observers viewed it two ways.

"He won, and he won handily," said city Controller Michael Lamb. "He beat either of his two opponents by more than 2-to-1. ... He's got a four-year term now, a fresh start, and hopefully he'll make good use of it."

Others latched on to big dips in support in African-American wards, and a 55 percent share that is historically low for a Democrat in the city.

"That shows that if you could field the right candidate, I think the machine is vulnerable," said the Rev. James Simms, a former Allegheny County councilman and pastor of St. Paul Baptist Church in Point Breeze. "There is a possibility that, if we had a couple of stronger candidates running, without being new to the game, I think the numbers could've turned out much different."

For 76 years, Democrats have won Pittsburgh mayoral elections. The lone asterisk sits beside the 1977 election, when Democratic Mayor Richard Caliguiri sat out the primary, then ran as an independent to beat Democratic nominee Tom Foerster.

Other than the 1977 race, no Democratic nominee has gotten less than 60 percent of the vote since 1945. The average share of the vote garnered by all Democratic nominees since 1933 is 65.9 percent.

"I would've expected over 60 from [Mr. Ravenstahl], to tell you the truth," said Joseph DiSarro, chairman of the political science department at Washington and Jefferson College, from which the mayor graduated.

"I think that the negative campaigning on behalf of his two opponents took a toll," Mr. DiSarro said. Will any resulting negative perception of the mayor endure? "I think it'll last only if the mayor has problems dealing with the policy issues facing the city."

The attacks -- which included Mr. Harris' argument that the mayor often skips events, and Mr. Acklin's contention that he's a puppet of developers -- will be noted by potential future challengers, said Mr. DiSarro.

Anyone intent on uniting the voting blocs won by Mr. Harris and Mr. Acklin would face challenges.

Whereas Mr. Harris swayed some reliably Democratic voters, Mr. Acklin appeared to get most of the same votes won by underfunded Republican Joe Weinroth in his 2005 mayoral bid, according to Chris Briem, a regional economist for the University of Pittsburgh's Center on Social and Urban Research, who analyzed the votes by precinct.

Some city hall wags were talking yesterday about two-challenger scenarios that would combine two mayoral weaknesses -- opposition among East End elites and soft support among African-Americans.

"If you combine the [independent candidates'] votes, [then the mayor] lost the 4th ward, the 7th ward, the 8th ward, the 11th ward, the 14th ward," said Morton Coleman, former director of the University of Pittsburgh's Institute of Politics. Those wards center on, respectively, Oakland, Shadyside, Bloomfield, Highland Park and Squirrel Hill, signaling weak support for the mayor among upper-middle-class East Enders.

If one doesn't combine the challengers' votes, the mayor won every ward.

Ward-by-ward, the mayor's biggest slippage, compared to his 2007 win over Republican Mark DeSantis, occurred in the largely African-American neighborhoods of the Hill District, Lincoln-Lemington and Homewood. After getting 9 out of 10 votes there in 2007, he got around 2 out of 3 there Tuesday. By and large, the lost votes went to Mr. Harris, who is black.

Maybe voters there wanted "to support a candidate with whom they felt closer in some way, or [voted as] an expression of discontent," said Allyson Lowe, chair of the Department of Political Science at Carlow University.

Those wards typically vote very heavily Democratic, and may do so again, she said. "Do I think [Tuesday's shift] portends anything for the [future] Democratic nominee? No."

Lukewarm support for the Democratic nominee, and low turnout, could portend something if those neighborhoods don't see increased opportunity, said Celeste Taylor, a project director for the Black Political Empowerment Project.

"I think people wanted more proven ability to bring about change," she said. "I think people are very hungry for change, and we hear a lot about how Pittsburgh is number one in this, and we're getting all of these jobs. I'm not seeing those jobs."

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