"When he took over, the country was in very, very difficult straits. We were in one of the worst recessions we had seen in recent times, close to a depression," Powell said. "We were in real trouble ... I saw over the next several years stabilization come back in the financial community, housing is now starting to pick up after four years."
In an interview on CBS' "This Morning," the longtime Republican said he respects Mitt Romney, but said he's been vague on many issues. He also said he was concerned with Romney's changing views on foreign policy.
Powell, who served as secretary of state from 2001 to 2005, praised the president for ending the war in Iraq and laying out a plan for leaving Afghanistan, adding that he "did not get us into any new wars."
"I think we ought to keep on the track that we are on," Powell said.
Powell crossed party lines in 2008 to support Mr. Obama. He said he is still a Republican, but said he was a "dying breed," a "Republican of a more moderate mold."
"This is my decision based on my looking at it as a citizen. I think this is an exciting race between two very, very capable men," Powell said.
Mr. Obama later called Powell to thank him.
The Associated Press contributed to this report.