THE OPEN RACE for Suffolk County district attorney is attracting a crowd, with five Democrats already in the hunt and several others still mulling a run for the post, which veteran prosecutor Dan Conley is giving up after 16 years in office.

The newest name to surface: state Sen. Joe Boncore, who said yesterday that he’s seriously weighing a run and will likely make a decision by next week sometime.

“I’ve seriously been considering putting my hat in the ring for the district attorney’s race,” Boncore told State House News Service. “Dan Conley had a great career as our district attorney and I think coming off the heels of the Legislature’s criminal justice reform bill the time is right for a district attorney who’s progressive, understands the new policies that need to come into place while still protecting and looking out for the public safety of all residents of Suffolk County.”

Those who say, “Joe who?” should know that many were asking the same question two years ago — until the Winthrop resident topped a seven-way field in the special election Democratic primary for the Senate seat he now holds.

Boncore, as a legislator just closing in on two years in office, is not particularly well known. But that was even more true when he emerged on top in the race for the Boston-based Senate seat, which includes East Boston, the North End, and a chunk of downtown neighborhoods, along with all of Revere, Winthrop, and a handful of precincts in Cambridge.

The key to his victory? While a slew of Boston candidates were slugging it out over votes in that part of the district, Boncore owned his hometown of Winthrop, where he won 65 percent of the votes in the seven-candidate field, and ran decently well in neighboring Revere, where he had to battle for votes against the city’s former mayor, Dan Rizzo.

A similar dynamic could play out in the DA’s race if Boncore decides to take the plunge. He could own the northern tier of Suffolk County, pulling big numbers in Revere and Winthrop, which he currently represents, as well as in East Boston and the North End, which, despite demographic change, both still claim a decent population of reliable Italian-American voters who could gravitate to a preferito figlio in the race.

Boncore, a former public defender, would join a race featuring lots of candidates focused on criminal justice reform. Already declaring their candidacies for the Democratic primary are state Rep. Evandro Carvalho of Dorchester, defense attorney Shannon McAuliffe, who ran a program for focused on gang-involved youth for Chelsea-based nonprofit Roca, Suffolk assistant district attorney Greg Henning, former Massport legal counsel Rachael Rollins, and real estate attorney Linda Champion.

With all the declared and would-be candidates looking to the already crowded Democratic primary, the race could effectively be decided by something far short of a majority of voters, a problem well-documented by voting activist Paul Schimek in this CommonWealth piece last fall. Boncore landed in the Senate by winning just 25 percent of the primary vote in low-turnout special election.

There are plenty of ideas on the table for election reforms to address the issue of “plurality victors” — candidates who win seats with far less than a majority of the vote. There won’t be any change in place for this fall’s DA race, however, and the current structure will suit Boncore just fine if he makes the jump.