Rep. Michael Capuano responded to rumors of a challenge from City Councilor Nadeem Mazen in next year’s primary election, which would pit two progressive democrats against one another in a district that represents most of Boston.

“It’s a free country, it always has been, and if Nadeem or anybody else wants to run, so be it,” Capuano said in an interview with Boston Public Radio on Thursday. “I’m not going to pretend to play the game that I want opposition, of course I don’t, but at the same time, I’m pretty comfortable with where we are, and we’ve got a lot of support across the district.”

The Boston Globe reported Wednesday that Mazen, a 33-year-old two-term city councilor and MIT graduate, is considering a run against Capuano, a 65-year-old congressman who has held his position, relatively uncontested, since 1998.

Capuano has represented the district including Somerville, Chelsea, Everett, Randolph and major parts of Cambridge, Milton and Boston, for 10 terms. He told BPR he plans to run again in 2018, though it’s not his highest priority at the moment.

“I am not going to focus on that for several months — it’s way too early for me to lose focus here,” Capuano said. “I’ll deal with elections when the election cycle comes around.”

Mazen, a two-term city councilor and the highest-profile Muslim elected official in Massachusetts, has previously expressed interest in running for higher office in 2018, though he has not officially confirmed a bid for Capuano’s seat.

According to Capuano, it doesn’t seem to matter who enters the race, or when they enter. “If I left for any reason, I think there would be 15 people in this race, just like it was before,” he said. “Fifteen good people, and — I don’t mean to be rude — I don’t care who it is, being first in the door won’t matter.”

“It will be a free-for-all,” Capuano continued. “Honestly, when I ran in ’98, I honestly don’t remember who was first.”

To hear Rep. Capuano’s full interview with Boston Public Radio, click on the audio player above.