"It's interesting that television really has swayed the conversation," Bartha said of the same-sex marriage debate. "You're just trying to make entertainment."
The comedy from "Glee" creator Ryan Murphy centers on engaged couple Bryan (Andrew Rannells) and David (Bartha) who, with the help of a surrogate, are expecting their first child.
The series uses humor to tackle social issues like homophobia and racism. Last week's episode examined the Boy Scouts of America's ban on gay members.
According to Bartha, it's only fitting that Tuesday's one-hour season finale features "a nice, big gay wedding," as the Supreme Court considers two landmark cases on same-sex marriage.
"It's coming on the heels of a very important decision," he said in an interview Friday in Los Angeles. "It's not often as an actor you get to be involved with a project that seems to be on the right side of history."
Another happy surprise for the 34-year-old "Hangover" actor has been becoming a role model.
"The feedback that we've gotten from young people has been inspirational," Bartha said. "People really look up to these characters and they have taken them on as really positive role models, which is something that I never thought about when taking on the project. You just want to do a good job, but it's really been quite a rewarding byproduct."
Though NBC has not announced whether "The New Normal" will be picked up for a second season, Bartha remains hopeful for the show's return.
"We're just now finding our footing with what we want to say and how we want to say it, and I think if we get the chance we'll do it even better (next season)," he said.