A new generation of Philadelphia City Council members were elected in Tuesday's primary, guaranteeing at least six fresh faces who could make or break Mayor Nutter's second term.

While Nutter cruised to victory over T. Milton Street, voters chose Democratic candidates in five hotly contested Council races and turned away GOP stalwart Frank Rizzo Jr.

Four districts with retiring incumbents will be represented by freshman council members in 2012, including Mark Squilla in the First District; Bobby Henon in the Sixth; and Cindy Bass in the Eighth.

The race in the Second remained too close to call last night, with just a handful of votes separating Barbara Capozzi and state Rep. Kenyatta Johnson.

Those candidates either face no Republican candidate in November or will be heavy favorites.

Councwilwoman Maria Quiñones Sánchez, cast by political observers as the underdog to retain her Seventh District seat, turned back Danny Savage, the man she snatched it from in the 2007 Democratic primary.

Sanchez said her underdog label was "symptomatic of the disrespect" shown to her and the community that supports her.

"I think we've demonstrated today that, not only in my neighborhood but throughout the whole district, that they were happy with my work," she said.

On the Republican side, the GOP will send two new at-large members to council after voters shockingly rejected Rizzo. The other Republican at-large member, Jack Kelly, is retiring.

Rizzo appears to have been a victim of the voter revolt against DROP, the controversial pension program that he and other elected officials were enrolled in.

"I knew it was an uphill battle," Rizzo said. "Listen, that's what elections are all about, they send a very clear message."

For once, all five Republicans vying for at-large seats in the general election are electable candidates - David Oh, Dennis O'Brien, Al Taubenberger and Joe McColgan, with Malcolm Lazin and Michael Untermeyer separated by a few votes for the last spot. The GOP at-large battle could be the most exciting in November.

The new Council members also could be pivotal in deciding who will be the next Council president, with the retirement of President Anna C. Verna.

Majority Leader Marian B. Tasco and Majority Whip Darrell L. Clarke are expected to vie for that spot, with Jannie L. Blackwell as a darkhorse candidate. All three easily beat their Democratic primary opponents Tuesday. None have Republican challengers.

The five Democratic at-large incumbents survived, turning back strong challenges from Andy Toy and Sherrie Cohen. The five Democratic nominees will almost certainly be elected in November as the top five vote-getters, with a better than 6-to-1 registration advantage over Republicans.

In the Second, with 98 percent of the precincts reporting, fewer than 100 votes separated Johnson, a two-term state representative, and Capozzi, a well-known South Philadelphia realtor and developer. They are battling to replace Verna in a district representing parts of South and Southwest Philadelphia.

The winner would face Republican Ivan Cohen in the fall as a heavy favorite.

Capozzi was a traditional ally of Verna's, but the Council president did not endorse a candidate in the race. Johnson burst on to the political scene in 2008, beating a 22-year incumbent to earn a seat in Harrisburg. He easily won reelection in 2010.

In the First District covering parts of South Philadelphia and the river wards, Squilla won in surprisingly easy fashion to succeed Councilman Frank DiCicco. No Republican is running there.

In the Sixth District in Port Richmond and the Northeast, Bobby Henon, the political director for the powerful Local 98 of the International Brotherhood of Electrical Workers, bested Marty Bednarek, a former School Reform Commissioner.

Both men had deep roots in the district, represented for more than 30 years by retiring Councilwoman Joan Krajewski, and each had strong bases of support and establishment endorsements.

But Henon raised an astounding amount of money - more than $624,000 - with heavy doses from political action committees associated with organized labor.

Bednarek had the backing of Krajewski and Mayor Nutter, but the unions and Gov. Rendell lined up behind Henon, who will face Republican Sandra Stewart in the general election.

"I had the best run campaign that I have seen ever," Henon said. "I think the message that I had out there resonated. When I was out there knocking on doors and meeting people in the street, they got the message."

In Northwest Philadelphia, Cindy Bass emerged from a field of seven candidates to replace Councilwoman Donna Reed Miller in the Eighth District.

Bass, a senior aide to U.S. Rep. Chaka Fattah, was running for the second time in a district that stretches from the city's richest neighborhood (Chestnut Hill) to some of its poorest (Tioga/Nicetown).

"This is a very fractured district and has been fractured for a long time," she said. "Now it's time to do the heavy work to bring those folks together. It's critical that we find a way to unite this district."

Bass was able to outlast her nearest competitors, including Howard Treatman, a wealthy businessman, and Verna Tyner, a former chief of staff to Councilman William K. Greenlee. Greg Paulmier, who twice finished second to Miller, again had a strong showing.

Treatman donated more than $250,000 of his own money to his campaign, triggering a provision that doubled the contribution limits for the other candidates.

Tyner secured the last minute backing of Miller, but the retiring councilwoman sparked an ethics investigation by releasing her endorsement on her council letterhead - a potentially impermissable mixing of city and campaign business.

With no Republican challenger, Bass becomes the councilwoman-in-waiting. She will join members Curtis Jones Jr. and Blondell Reynolds-Brown as Fattah proteges on council.

Councilwoman Blackwell, representing the Third District in West Philadelphia, crushed Tony King. Curtis Jones Jr., whose Fourth District covers West and Northwest Philadelphia, ran unopposed and does not have a Republican opponent.

Republican Brian O'Neill, representing the 10th District in the Northeast, was unopposed, and will face Democratic challenger Bill Rubin in the general election.

Contact staff writer Jeff Shields at 215-854-4565 or jshields@phillynews.com.