The Fauxbama also wed lookalikes of conservative figures Michele Bachmann and Sarah Palin in the campaign from BeautifulPeople.
BeautifulPeople is a controversial dating website which claims to feature only attractive people among its community.
The site states that its billboards have been "banned across America", leading to the spoofed figures being censored.
A billboard truck featuring the uncensored campaign images was recently parked outside Trump Towers.
BeautifulPeople's managing director Greg Hodge said: "BeautifulPeople.com is a big supporter of gay marriage. We wanted to poke fun at the politicians that are stuck way back in the middle of the last century.
"We created the images using lookalikes. I am confident Barack Obama would have been happy to take part in the campaign himself, but we didn't want to trouble the president as he is very busy.
"I'm sure Sarah Palin has a bit of time on her hands, but I don't think she would have been quite so willing to take part."
The company has pledged to give 15% of its proceeds from every same-sex membership to a non-profit group supporting marriage equality.
Last year, eBay pulled a charity auction from BeautifulPeople offering a date with scantily-clad takes on Joseph and the Virgin Mary.