The former America's Next Top Model finalist, 25, and McDorman, 28, were spotted kissing during their viewing of the US Open at the USTA Billie Jean King National Tennis Center in New York in late August, Us Weeklyreported.
The couple are currently in New York City filming the new ABC TV series Manhattan Love Story, which is set to premiere Tuesday, September 30 at 8:30PM ET/PT.
Although Tipton had gotten engaged to her boyfriend Aaron McManus in late December of last year after six years of dating, a source insists McDorman had nothing to do with why that relationship ended.
"She did not break off her engagement for [Jake]," the source told Us.
Since her stint on Top Model, Tipton has appeared on numerous TV shows and movies, including The Big Bang Theory and Crazy, Stupid, Love.
News Tipton would be starring in a pilot for Manhattan Love Story first surfaced in January although the series was still untitled at the time. The comedy will expose the unfiltered internal monologues of a young couple, Peter and Dana -- a pretty and friendly character played by Tipton -- as they begin a new relationship. Watch a trailer for the new TV series below.