Longtime incumbent Bill Galvin will have a chance to debate his challenger Josh Zakim in their first and only scheduled televised debate in the secretary of state’s race before the primary election three weeks from today.

Quick context: in Massachusetts, the secretary of the Commonwealth is elected every four years to oversee elections, the public records division and historical commission, among others. The secretary of the Commonwealth’s office also makes it so that the public can access public information — like employee’s salaries. For instance, the secretary’s salary in 2017 was $146,525.77.

Galvin oversaw the implementation of the “Motor Voter Law,” which has become the most popular way for people to register to vote because of it’s convenience. The law allows people as young as 16 to register to vote or update their registration on forms at the RMV.

Galvin, who was sworn into the office in 1995, pledged at the time to "seek to open as wide as possible to meaningful participation by citizens the processes that affect our daily lives."

This is only the second time that Galvin has had a Democratic challenger, and he waited until the day before the debate to agree to appear.

Zakim has served as a Boston City Councilor representing Back Bay, Beacon Hill, Fenway, Kenmore Square, Mission Hill, Audubon Circle, and the West End since being elected in 2013. At the state Democratic convention in June, Zakim won the party’s endorsement.

Throughout the campaign, Zakim has tried to brand himself as the more progressive candidate with a focus on access to voting. He’s pointed to the state’s abysmal voting turnout as a sign of his opponent’s shortcomings.

He’s pushing for changes to the way people in Massachusetts vote including adding same-day registration and weekend elections.

The debate will air at 7 p.m. on WGBH and will be moderated by Greater Boston’s Jim Braude.