Gibbs spoke Monday night at Union College in Schenectady, N.Y., giving a talk titled "Inside Washington: What's Next," WAMC-FM reports. Gibbs is expected to be a consultant to President Obama's campaign for re-election next year.
Before his speech, Gibbs talked to reporters about the race. He said Romney, who served one term as governor of Massachusetts, is most likely to win the nomination, but former Arkansas Gov. Mike Huckabee might be a stronger candidate in the general election.
One potential candidate Gibbs has little use for is Donald Trump, USA Today said. He attacked Trump's embrace of the "birther" notion that Obama was not born in Hawaii.
"If he thinks he can build a campaign on the president's birth certificate, I don't think he will be hired by the American people," Gibbs said. "In the end, I don't think he runs."
Gibbs acknowledged Obama has a tough campaign in front of him. He predicted a close election because of the lingering economic slump.