North Andover voters get a rare front-row seat to history next week, when six Democrats vying for Massachusetts' 6th Congressional District square off at the Worden Theatre — a race that hasn't had this kind of opening in nearly half a century.

Why this race is such a big deal locally.

The North Andover Democratic Town Committee hosts "Mass 6th District Decides" on Tuesday, July 28, at 6:30 p.m. at the North Andover Historical Society's Stevens Center, right across from the town common. The seat covers North Andover and Andover, and it's been held continuously without an open contest since the late 1970s — Republican candidate Micah Jones has put the number at 47 years. That kind of rarity means whoever comes out on top this fall could be settling into the job for a long time.

Who's making the case for your vote.

Six Democrats are scheduled to appear: Beth Andres-Beck, John Beccia, Jamie Belsito, Dan Koh, Mariah Lancaster, and state Rep. Tram Nguyen of the 18th Essex District. All six are competing for the seat Rep. Seth Moulton is vacating as he runs for U.S. Senate against incumbent Sen. Ed Markey — a domino effect that's opened up one of the most competitive local races in years.

Getting in the door.

Seats are limited, so the town committee is asking attendees to RSVP through a Google Form linked on the event's Patch listing. Details on the forum's format, moderator, and whether it's open to voters regardless of party registration haven't been published yet — worth a call ahead if that matters to you.

With five weeks left before the Sept. 1 primary, this may be one of the last chances for North Andover voters to see the full Democratic field in one room before ballots are cast.