President Obama said Tuesday that the difference in Iran between hard-liner Mahmoud Ahmadinejad and reformist Mir Hossein Mousavi "may not be as great as advertised."

In an interview with CNBC, Obama also said the ongoing protests in Iran show that he voters there are not convinced of the election results.

Regardless of the outcome of the disputed election in Iran, Obama said the U.S. has a long-term interest in preventing Iran from weaponizing nuclear power, and funding militant groups Hezbollah and Hamas.

Earlier Tuesday Obama said the Iranian election revealed a change in expectations among voters and perhaps their leaders. He said he was deeply troubled by the election and its aftermath but stopped short of saying the re-election of hard-liner Mahmoud Ahmadinejad was rigged.

"I do believe that something has happened in Iran," with Iranians more willing to question the government's "antagonistic postures" toward the world, Obama said.

"There are people who want to see greater openness, greater debate, greater democracy," he said during a Rose Garden news conference.

He said nothing about the declared winner, Ahmadinejad, or his pro-reform challenger whose supporters claim the election was stolen.

"It's not productive given the history of U.S.-Iranian relations to be seen as meddling," Obama said.

After deadly protests in Tehran on Monday, with demonstrators holding signs that read "Where Is My Vote," the clerical regime organized a counter-rally Tuesday. The government also said it would recount some ballots but would not declare last Friday's voting void.

Obama said Iran's powerful religious chief, who is more influential than the president, appears to understand the dissatisfaction in his country.

"You've seen in Iran some initial reaction from the supreme leader that indicates he understands the Iranian people have deep concerns about the election," Obama said.

Supreme Leader Ayatollah Ali Khamenei said Monday that the government would conduct an investigation into the election. The move seemed intended to calm protester anger but was followed by a rally of hundreds of thousands of people that presented one of the greatest challenges to Iran's government since it took power in the 1979 Islamic Revolution.