Boston voters on Tuesday will pick their first new mayor in two decades, choosing between state Representative Martin J. Walsh and City Councilor John R. Connolly after a compressed campaign that grew increasingly acrimonious in its closing weeks.
Walsh and Connolly have dueled over whose supporters have fought more dirtily, and they have argued over shadowy telephone calls and negative fliers. The embittered tone has largely papered over the fact that the policy differences between the two are thin.
Walsh, a Dorchester Democrat, has taken pains to emphasize that he, too, favors education reform and an increased number of charter schools. Connolly, a West Roxbury Democrat, in recent weeks has proclaimed that he is pro-union, pointing to his votes in favor of nearly all public employee union contracts that have come before the council.
With both candidates in possession of strong political bases in the city’s outlying neighborhoods, the election could hinge on the geographic middle of the city. Walsh and Connolly emerged in September from a 12-candidate field spread across the city, leaving a large number of voters up for grabs.
Early polls in the race gave Connolly the lead, but Walsh built momentum by lining up support from a diverse array of elected officials, and gained the backing of the September preliminary election’s top three finishers of color: Charlotte Golar Richie, Felix G. Arroyo, and John F. Barros.
Walsh has also benefited heavily from outside groups spending on his behalf, roughly $2.5 million from groups mostly backed by labor. Outside groups have spent $1 million on Connolly’s behalf, most of it from Democrats for Education Reform, which is funded largely by a New York nonprofit that does not disclose its contributors.
Tuesday’s election also marks a closing chapter in the city’s political history. Mayor Thomas M. Menino, the city’s longest-serving mayor, announced in March that he would step down, uncapping years of simmering ambition among Boston’s political class.
Walsh told reporters he had called Menino on Monday to ask for his vote, and he pushed back against Connolly’s suggestion that many of his supporters hail from outside the city.
“The people on the ground are my campaign and we have volunteers from all over the city of Boston,” Walsh said.
Shaking hands Monday at the Forest Hills T station, Connolly said, “This thing is a jump ball. Every last voter interaction counts.”
Whichever candidate prevails will inherit a vastly changed city than the one Menino took over in 1993, when Raymond L. Flynn left to become US ambassador to the Vatican. The city’s population has grown more diverse, many of its long-simmering racial tensions have subsided, its physical development has reached into new areas like the South Boston waterfront.
And, as the city’s sports fans were reminded last week and again on Saturday, it’s now a town that with good reason sees itself as a winner.
The Red Sox victory parade, which forced campaigns to skirt traffic and try to wrest toward politics the attention of distracted fans, provided a second bookend for the race. The roster of candidates was still taking shape in April, when the Marathon bombings rattled the city and dominated news coverage.Wesley Lowery and Joshua Miller contributed to this report. Jim O’Sullivan can be reached at Jim.OSullivan@globe.com. Follow him on Twitter at @JOSreports.