Turnout is the key:

Here’s the paradox of the 2013 Boston mayoral primary: the field of 12 candidates has yielded one of the most thoughtful and measured campaigns that I have ever covered. Still, turnout is expected to be low. Hopes that as many as 25 percent of the city’s 365,000 registered voters would go to the polls have been scaled back. If 20 percent of the electorate were to turn out, political professionals would consider that strong. Some experts, however, think turnout could go as high as 35 percent. If that were to happen, it would be attributed to the sheer number of candidates rousting their votes.

Admittedly, it is difficult for an average voter to keep track of a campaign this sprawling. But if history is any guide, the number of candidates running has little to do with voter participation. Boston municipal primaries do not compel the same level of interest that statewide or national elections do. The progressive voters who turned out to elect Deval Patrick governor and Barack Obama president traditionally do not feel the same compulsion to cast ballots for mayor. It is an oddity, for sure. Whoever runs City Hall is more likely to have an immediate impact on individual lives than either the president or governor. Go figure.

Despite the profusion of new ideas, the widespread employment of social media, and the infusion of new names and faces into the political process, this election will be decided the old-fashioned way: by identifying voters and getting them to the polls.

A new generation:

Not only will this election bring about the first change of mayor in 20 years, it will also usher a new generation into municipal power. Just before he leaves office, Mayor Thomas Menino will turn 71. The average age of Menino’s replacements is 49. At 59, Bill Walczak is the oldest candidate; City Councilor At Large Felix Arroyo at 34 is the youngest.

Regime change:

When Boston Police Commissioner Ed Davis announced Monday that he would step down before a new mayor is sworn in, the fact that big changes would be coming finally began to sink in. The resignation months earlier of School Superintendent Carol Johnson had already been digested. That the new mayor would have to fill the two most challenging and potentially thankless jobs sobered those who could lift their heads above the fray of the campaign.

Insiders knew that Davis was planning to leave. But speculation among the general public about which candidates might deign to keep Davis on the job must have galled the well respected but increasingly embattled commissioner.

Davis’ resignation the day before the primary was two-pronged. It was tactical: Davis took himself out of the running before a candidate who wanted him replaced potentially reached the finals. And it was also strategic: “You think this job is a piece of cake, see how tough it is once I’m gone,” struck me as an unspoken but very plausible message on the part of Davis. The bottom line: Boston is in for much bigger changes than most people realize.

Who's on first?

Polls show that the race is tight. So close, that there is the potential for an upset. With that in mind, here is how the candidates stack up: City Councilor At Large John Connolly of West Roxbury is considered the front-runner, by a narrow margin. Connolly is followed by a field of three, one of whom is expected to take the second slot: Suffolk County District Attorney Dan Conley, also of West Roxbury; State Rep. Marty Walsh of Dorchester; and Charlotte Golar Richie, a former elected and appointed official who also lives in Dorchester.

This first cohort is followed by City Councilors Mike Ross, Rob Consalvo, and Felix Arroyo; former School Committee member John Barros; and longtime Dorchester activist and health care executive Bill Walczak. With a little luck and a lot of organizational skill, one of these second-tier five might be able to knock out one of the first-tier four.

Race, class and gender:

With the 2010 census Boston became a majority-minority city. Simply put, that means that minority residents taken as a single group outnumber white residents. Due to a number of factors, that’s a trend that is only going to intensify in coming years. Not surprisingly, there are a record number of minority candidates: Arroyo (Latino), and Golar Richie, City Councilor Charles Yancey, Radio executive Charles Clemons, and Republican David James Wyatt (African American), and Barros (whose parents immigrated from Cape Verde).

In my view, the so-called minority field offers the most interesting subtext of the election. Golar Richie is the standard bearer of the established black middle and professional classes. Yancey is representative of blue collar black Boston. And Arroyo and Barros are stalking horses for a growing generation of reformers whose base might be ethnic, but whose appeal is more broadly based.

As for gender, there is no doubt that women are under represented in Boston politics. As a result, Golar Richie attracted more interest in the last days of the campaign in part because she is the only woman running. It is worth noting that two of Menino’s past opponents were indeed women, Peggy David Mullen in 2001 and Maura Hennigan in 2005. Looking beyond this election cycle, City Councilor At Large Ayanna Pressley, and State Senator Linda Dorcena Forry, both of Dorchester, are viewed as potential mayoral hopefuls – as is Michelle Wu, who is seeking office for the first time with her high-energy run for a council seat.

Learn more about each of the 12 mayoral candidates here.