As tomorrow’s Democratic primary approaches, New Haven Mayor John DeStefano Jr. and his challenger Sherri Killins are focusing their attention not only on their own races, but also on several primaries that may change the face of the Board of Aldermen.

DeStefano is actively supporting candidates in 16 races, whose outcome will likely prove an important test of the city’s confidence in the mayor’s administration. If his efforts are successful, DeStefano’s most outspoken opponents on the board may find their seats occupied by allies of the administration next year.

DeStefano’s campaign manager, Shonu Gandhi ’03, said the mayor has chosen to take a more direct role in this year’s aldermanic primaries than he has in past elections, endorsing nine candidates who are running for their first term in office and four who are challenging incumbent Democrats.

“In this election particularly, there is a stark contrast between the kind of politics we want to pursue and the kind of politics our opponents practice,” said Gandhi, a former Yale Daily News staff columnist. “We want to be part of changing the politics of the city.”

Killins, on the other hand, said the number of races reflected a desire of New Haven citizens to challenge a mayor who has “ostracized” his political opponents.

“You have 17 different aldermanic races, which is a sign of the discontent in the community,” said Killins, a former CEO of the community development group Empower New Haven. “That’s why we need a Board of Aldermen that is going to fight for and represent the community, and not just agree with the mayor.”

Unlike DeStefano, Killins has not formally issued endorsements for Tuesday’s primaries, although she said she was “clearly” working closely with several candidates.

The New Haven Democratic Town Committee — the local Democratic party organization — issued formal endorsements of candidates in July after reviewing the recommendations of the party’s committees in each aldermanic ward. But Democrats who received signatures from 5 percent of registered Democrats in their wards are still eligible to run in the primary.

As a result, 17 candidates who were endorsed by the town committee are facing challenges for the Democratic nomination and, in many cases, an unopposed run in November’s general election. With more contested Democratic primaries this year than in any year since 1989, both DeStefano and Killins have become important figures in the ward-by-ward races to determine the composition of the next Board of Aldermen.

New Haven Democratic Town Committee Chairwoman Suzie Voigt said DeStefano has played an important role in his efforts to change the Board of Aldermen, especially in his support of several political newcomers.

“This is a group of people who see themselves as a team. That doesn’t mean they agree on every issue, but they are going to work together,” Voigt said.

Nowhere is the involvement of DeStefano and Killins more evident than in Ward 28, where former police commissioner Babz Rawls Ivy is challenging incumbent Brian Jenkins. Jenkins, who has frequently challenged DeStefano from his post as chairman of the board’s Black and Hispanic Caucus, has been closely allied with the Killins’ campaign since she decided to run for mayor earlier this summer.

On official Board of Alderman letterhead, Jenkins distributed a letter this weekend in the Hill neighborhood entitled “John DeStefano Is Killing Our Community!” that charged the mayor with wasting $15 billion in taxpayers’ money.

“After 10 years of John DeStefano what has The Hill gotten?” read the letter, which was reprinted by the Killins campaign. “Blighted properties, unemployment, crime and even higher taxes! Yet he continues to get your vote — and laughs behind your back.”

Ivy, who has been endorsed by the mayor and by the Democratic Town Committee, said that while the focus of her campaign has been on issues like bringing sidewalks and community centers to her neighborhood, the mayor’s support has helped shape her campaign.

“People ask, ‘Are you supporting the mayor?'” Ivy said. “And when you say yes, they say, ‘Yeah, you’ve got my vote.'”