If the public opinion polls are correct, the momentum in the presidential race has swung toward Barack Obama.

The Democratic presidential nominee has been taking no chances on the campaign trail, the Associated Press notes, providing measured policies to deal with the financial crisis and other issues. He is letting others respond to Sen. John McCain's more vigorous attacks.

Campaigning with Sen. Obama in Ohio last week, Sen. Sherrod Brown, D-Ohio, deflected with larger concerns Republican charges about Mr. Obama's relationship with Vietnam-era radical William Ayers, now a college professor in Chicago. "People are saying, 'What about our jobs, what about the banking situation?'" Sen. Brown said.

Also counterattacking, Delaware Sen. Joseph Biden, Democratic vice presidential nominee, told a crowd in Springfield, Mo., Friday that Sen. McCain is trying "to take the lowest road to the highest office in America."

When Sen. Obama does respond to such attacks from Sen. McCain and vice presidential nominee Sarah Palin, he says the tactics will not work, that they are acts of desperation and that Americans need leadership to unite rather than divide the country.

On questions of policy, Mr. Obama is taking a careful approach as well, explaining his proposals for tax cuts and energy investments, and adding other proposals such as tax breaks and low-interest, government-backed private loans for troubled small businesses.

Thus, the Democratic nominee is reading his speeches more these days to avoid mistakes, the AP reports, prefers one-on-one interviews with reporters rather than press conferences and is generally exercising caution.

That is the dynamic right now, rooted in the perception that the Democrat is leading substantially. It places a lot of faith in the polls, which can be wrong. Chances are, Sen. Obama's tactics will change as Election Day nears. But for the moment, he is taking a measured approach.