While the world waits for  potential Republican candidates to decide whether they are in or out of the 2012 presidential race, Florida Senator Marco Rubio is leaving no room for speculation.

“I am not running for president in 2012. Because I want to be a United States senator. I want to be the best United States senator that Florida has ever had,” Rubio said in an interview on ABC’s “Nightline.”

“I just got elected three months ago so how can I be a full-time United States senator if my eye’s already on running for  something else?”

Rubio, the biggest Tea Party success in the 2010 congressional elections, has said it before — he’s not considering a presidential bid at this point in his career.

But that didn’t stop ABC’s Jonathan Karl from pressing the issue  during the Florida freshman’s “first national television interview” since being elected.   (The new senator was doing his “first live network interview on “Good Morning America” on Wednesday.)