"The more upbeat tone and the change in the unemployment forecast will only encourage expectations for action soon," Jim O'Sullivan, chief U.S. economist at High Frequency Economics, wrote in a research note. "We continue to believe that tapering could start at the Sept. 17-18 meeting."
But David Robin, co-head of the futures and options desk at the brokerage Newedge, said he didn't think Bernanke's upbeat assessment matches an economy that's just "muddling along."
Investors may suspect the Fed is looking for a reason to scale back the bond purchases, Robin said. "It's a big mess," he said.
The statement was approved on a 10-2 vote. James Bullard, the president of the Federal Reserve Bank of St. Louis, objected for the first time this year, saying he wanted a stronger commitment from the Fed to keep inflation from falling too low.
Esther George objected for the fourth time this year, again voicing concerns about inflation rising too quickly.
During his news conference, Bernanke declined to address speculation that he will step down as Fed chairman when his term ends in January.
He was asked to respond to comments Monday by President Barack Obama, who said Bernanke had already stayed longer than planned. The president's remarks added to expectations that Bernanke intends to step down.
Bernanke avoided the question.
"I would like to keep the discussion on monetary policy," he said. "I don't have anything for you on my personal plans."
The ultra-low rates engineered by the Fed have helped fuel a housing comeback, support economic growth, drive stocks to record highs and restore the wealth America lost to the recession.
Financial markets have been gyrating in the four weeks since Chairman Ben Bernanke told Congress the Fed might scale back its effort to keep long-term rates at record lows within "the next few meetings"-- earlier than many had assumed.
Bernanke cautioned that the Fed would slow its support only if it felt confident the job market would show sustained improvement. And he also told lawmakers that the Fed must take care not to prematurely reduce its stimulus for the still-subpar economy.
The Fed announced after its September meeting that it would purchase $40 billion a month in mortgage bonds for as long as it deems necessary. And in December, the Fed expanded the program to $85 billion a month, adding $45 billion a month in Treasury bond purchases. The Treasury purchases replaced an expiring bond-purchase program.
Job growth picked up after the Fed announced the latest round of bond purchases. Since October, the economy has added an average of 196,500 jobs a month, up from 157,000 a month in the previous eight months.
Last month, the U.S. economy added a solid 175,000 jobs. But the unemployment rate is still high at 7.6 percent. Economists tend to regard the job market as healthy when unemployment is between 5 percent and 6 percent.