Expressions of support and a candidates’ gathering in South Boston helped fill the First Suffolk District state Senate campaign calendar over the last week.

A group of elected officials from Boston signaled support for Dorchester’s state Rep. Linda Dorcena Forry’s bid as the Dorchester-based firefighters’ union threw its weight behind South Boston’s state Rep. Nick Collins.

State Sen. Sonia Chang-Diaz, a Jamaica Plain Democrat, turned out for a Saturday morning Dorcena Forry rally at the Phillips Old Colony House, as did Suffolk County Sheriff Steve Tompkins, City Councillors At-Large Ayanna Pressley and Felix Arroyo, and District Seven Councillor Tito Jackson.

Days earlier, Collins, a fellow Democrat running for the seat left open by former state Sen. Jack Hart, touted the support of Boston Firefighters Local 718. The union, which called Collins an “honorary member,” has about 2,400 members and offices in the Neponset neighborhood’s Florian Hall.

“We are proud to endorse Nick Collins and look forward to working with him to defend working families and our right to collectively bargain,” Rich Paris, the union’s president, said in a statement.

The Democratic primary, which will also include South Boston entrepreneur Maureen Dahill, is set for April 30. The winner will face off against Dorchester native Joseph Ureneck, a Republican, in the May 28 special election.

The four candidates for the Senate seat, which opened up after Hart left to join a law firm, appeared together on Tuesday at the monthly meeting of the South Boston Association of Non-Profits.

The lightly attended meeting was one of several stops this week for the candidates, who also made appearances at civic associations in Clam Point and Cedar Grove.

At the nonprofits’ session, the candidates fielded a question about the upcoming St. Patrick’s Day parade in South Boston. Organizers have frequently clashed with gay and lesbian groups over whether the groups can march in the parade. A 1995 Supreme Court ruling says the organizers, the Allied War Veterans Council, are entitled to choose which groups march in a parade it is sponsoring.

Earlier in the month, Dahill, a South Boston native, was the first among the candidates to call for gay and lesbian groups to march in the Council’s parade. At the forum, she said the traditional South Boston parade should “reflect the neighborhood [South Boston] is today” and expressed hope that organizers would change their mind before the parade this coming Sunday. Dahill has also launched an online petition to press her point, and as of late Tuesday, it had gathered 165 signatures.

Dorcena Forry, who is married to Reporter publisher and editor Bill Forry, said she agreed with Dahill, and called South Boston an “inclusive community.” She will not be marching this year, citing the exclusion of gay and lesbian groups, and has not marched while she has been a state representative over the last eight years.

Collins told the nonprofit forum’s attendees that he agrees with the Supreme Court decision, but that he will be marching along with gay and lesbian supporters of his campaign.

Ureneck has said the Supreme Court case is “settled law,” and on Tuesday he noted that he has had requests to march as part of a fathers’ rights group turned down by the parade organizers.