Credit: Kevin Mazur/

Alec Baldwin didn't go stag at Sunday's Tony Awards in NYC.

Instead, the 30 Rock star and potential NYC mayorial candidate, 53, hit theater's biggest night with Hilaria Thomas, a stunning 28-year-old yoga teacher.

Backstage, one witness saw Baldwin grab Thomas' booty as they chatted up Kelsey Grammer. Baldwin and NYC-based Thomas were first spotted together at Carnegie Hall in May, with numerous follow-up dates at high-profile bashes in NYC.

Although an insider says that Baldwin (whose marriage to Kim Basinger ended bitterly) is committed to staying single, his being so public with Thomas "makes me think it might be a little more serious."

Tell Us: Do Baldwin and Thomas make a cute couple?