District 37 Democrats vying for the chance to replace one of New Jersey’s political titans will meet for their first debate in an increasingly acrimonious primary Sunday.

After more than a decade running on the same ticket, Assemblyman Gordon Johnson (D-Englewood) and Assemblywoman Valerie Vainieri Huttle (D-Englewood) now find themselves locked in an intra-party contest to replace Senate Majority Leader Loretta Weinberg (D-Teaneck) in the upper chamber.

Weinberg is not seeking re-election this year, and both of her district mates want to succeed her. Johnson and his running mates, former Tenafly Councilwoman Shama Haider and former Englewood Cliffs Councilwoman Ellen Park, have the support of the Bergen County Democratic Committee and the preferential ballot position that comes with it.

Vainieri Huttle, Teaneck Councilwoman Gervonn Romney Rice and Tenafly Councilwoman Lauren Kohn Dayton, her running mates, are seeking a primary win off-the-line in the overwhelmingly Democratic district.

What started as a contest between longtime running mates has morphed over time into a bitter fight for the Democratic nomination tantamount to a general election victory.

Vainieri Huttle on Thursday pressed Johnson to respond to sexual harassment allegations lodged by a Englewood political leader who said the assemblyman told her she should become his “concubine” if she wanted to advance in local politics.

She’s previously attacked Johnson over guns, claiming he pandered to gun rights advocates when he told New Jersey Second Amendment Society that Weinberg was “more liberal than I am” on gun control eight years ago.

The assemblyman has a 0% rating from the National Rifle Association, and their voting records are virtually identical.

The Assemblyman hasn’t taken to the offensive in the same way Vainieri Huttle has. With organizational support breaking heavily in his direction he doesn’t have to.

His campaign has the endorsement of some of the state’s top Democrats, including Gov. Phil Murphy, Weinberg and Reps. Josh Gottheimer (D-Wyckoff) and Bill Pascrell (D-Paterson).

Vainieri Huttle isn’t without her own supporters. She has the endorsement of the Communications Workers of America, one of the state’s largest and most politically influential labor unions and progressive groups like Garden State Equality and the New Jersey Working Families Alliance.

But instead of attacking his once running mate, Johnson’s campaign has already turned its focus to the general election, hitting Bergen Republicans over Assembly candidate Edward Durfee, Northern New Jersey regional director of the Oath Keepers, a right-wing militia group marked as a domestic terror threat by Gov. Chris Christie’s Department of Homeland Security.

The Demographics of the 37th district — it has 55,075 more Democrats than Republicans in a district with just 156,013 registered voters — mean the Democratic primary is the real contest.

The debate between the two, sponsored by the New Jersey Globe and moderated by Globe editor David Wildstein, will be held at 9 PM Sunday, May 2. The event will be livestreamed to the New Jersey Globe website and its social media platforms, Facebook, YouTube and Twitter.