Washington (CNN) - For the record, it's still no. But is Florida's Republican Sen. Marco Rubio leaving his vice presidential options open? Consider how he answered the question Thursday to CNN.
"My answer hasn't changed on the vice presidential stuff. I know people keep asking me but my answer hasn't changed," Rubio told CNN one day after announcing his endorsement of GOP frontrunner Mitt Romney.
– Follow the Ticker on Twitter: @PoliticalTicker
If his answer hasn't changed, that certainly applies to now. But could his response change tomorrow or three months from now?
Last May, on NBC's "Meet the Press," Rubio said "under no circumstances" would he appear on the 2012 Republican ticket.
Asked whether that Shermanesque-sounding "under no circumstances" response still applies, Rubio told CNN, "Yeah, I'm not going to be the vice president." The smiling senator did not elaborate further.
Rubio offered a stout defense of his endorsement, noting Romney's main rivals, Rick Santorum and Newt Gingrich have all but pinned their hopes on a contested convention.
"They have said the only way they can win is in a floor fight in Tampa. I think a floor fight in Tampa is the worst possible thing we can do in terms of winning in November," Rubio said.
Rubio also echoed Romney's criticism of the president's open-mic moment with Russia's Dmitry Medvedev.
"When you have the president telling a foreign leader to work with him because he'll have more flexibility after he's elected, I think it's a worrisome indication," Rubio said. "Not just on foreign policy but what others issues does the president intend to pursue his flexibility on once the election is over?"
Putting Rubio on the ticket is widely seen as one of Romney's few existing plausible options for closing the GOP's favorability gap among Latino voters.
Rubio told CNN he would like to see the Republican Party repair its image on the issue of immigration. During the primaries, Romney has taken a hawkish stance on illegal immigration. But Rubio said he is comfortable with Romney's position on the issue.
"I think he believes in the pro-legal immigration system and so do I," Rubio told CNN.
"I think that's what the Republican Party needs to increasingly be sure people know – that is we are the pro-legal immigration party," he added.