ST. LOUIS • The goal on election day, according to Mayor Francis Slay’s campaign manager, was to get 21,000 pro-mayor voters to the polls.

And they would have to come not only from Slay’s strong base in the southwest portion of the city, but also from the central corridor — offsetting the mayor’s weakness in northern parts of the city.

The strategy paid off Tuesday, according to ward-by-ward election data, putting Slay on the verge of a historic fourth four-year term as mayor. Slay, the data show, built his 10-point re-election victory over Lewis Reed with a high turnout in his base and just enough support in other areas. In fact, Slay surpassed his campaign goal, with almost 24,000 voters casting ballots for him.

Slay this year faced his strongest challenger yet, after cruising to re-election in previous campaigns. In 2009, Slay garnered nearly 62 percent of the vote when his main challenger was former Alderman Irene Smith and turnout was much lower. On Tuesday, Slay earned 54 percent of the vote against Reed.

Voters in the southwest St. Louis wards running from Interstate 44 south to Interstate 55 showed up in the biggest numbers — and they went solidly for Slay. For example, Slay won 85 percent of the vote in the St. Louis Hills neighborhood’s 16th Ward, where more than one-third of registered voters turned out to vote, the city’s highest rate. That alone accounted for 2,400 votes for the mayor.

“We started identifying (voters) early, June 2012,” Slay’s campaign manager, Richard Callow, wrote in an email Wednesday. “We stayed on message. We did not get distracted by the other campaigns’ dynamics or messages.”

The push to victory had a helping hand from the central corridor, which runs straight through the city along Highway 40 (Interstate 64), from downtown to Skinker Boulevard.

The 28th Ward, which includes the Central West End and Skinker-DeBaliviere neighborhoods, favored Slay with 74 percent of the vote. Downtown and Soulard went for Slay, with 67 percent of the votes going to the mayor. Slay even narrowly won the 6th Ward, where Reed lives and which he once represented on the Board of Aldermen.

Reed won those wards, and the corridor as a whole, when he ran citywide in 2007 against Jim Shrewsbury to become president of the Board of Aldermen.

The area includes many wealthier, younger and liberal-minded voters. And they are often swing voters in municipal elections. To reach them, Slay’s campaign targeted dog lovers, gays and young professionals, and also touted issues such as rehabbed buildings, food trucks and smoke-free bars and restaurants.

“We were able to remind people about their city, about the mayor, and in many cases teach them about Lewis before he could,” Callow said in an interview.

Reed said Wednesday he didn’t have the money to get his message to those voters. Slay raised more than $3 million. Reed raised about $626,000.

“The attack ads he ran on me worked in the central corridor,” Reed said.

Reed focused his campaign in the last month on crime and targeted voters in north St. Louis. He appeared to abandon his early campaign strategy of targeting younger voters and those in the central corridor. An early campaign video showed Reed biking to work at City Hall. But by the final weeks of the campaign, that more relaxed, youthful image was replaced by a stern Reed standing on the steps of City Hall surrounded by unions and government workers denouncing various Slay policies.

Still, Reed said he had few regrets.

“I think we ran a good race, and I think it was a fairly close race,” he said.

Reed also said the impact of U.S. Rep. William Lacy Clay turned out to be minimal. Slay had secured the endorsement of Clay, as well as a strong partnership with state Sen. Jamilah Nasheed. Both are black and were viewed as key allies, especially in north city, for a race that pitted a white mayor against a black challenger in Reed.

“I don’t think Clay’s name made much of a difference,” Reed said. “You don’t see that in the numbers.”

Reed, in fact, won all of the north city wards.

David Kimball, a political science professor at the University of Missouri-St. Louis, noted that the “turnout in north city appears to be closer to the turnout in south city, at least as compared to previous city elections.”

But Slay benefited from the monster turnout in a few of his most loyal wards. Reed had no ward in the north that turned out for him in as big of numbers. His best showing was in the 21st Ward, where almost 24 percent of registered voters turned out, totaling about 1,500 votes.

In the end, Kimball said the election “was a referendum on the mayor’s job performance. I suspect that when we look at the exit poll results, we will find that a majority of St. Louis voters have positive evaluations of the mayor and the direction of the city.”

David Hunn of the Post-Dispatch contributed to this report.

Follow reporter Nick Pistor on Twitter at www.twitter.com/nickpistor

Nicholas J.C. Pistor is a reporter for the St. Louis Post-Dispatch.