In an editorial posted on its Web site, the Tribune said the country needs a president who can lead it through a "perilous time" and restore "a common sense of national purpose." Obama is the best candidate to do that, the editorial board said.
"We have tremendous confidence in his intellectual rigor, his moral compass and his ability to make sound, thoughtful, careful decisions," the Tribune said. "He is ready."
The Tribune said it liked Republican presidential nominee John McCain, but added that it's "hard to figure John McCain these days."
The Times, the country's fourth-largest newspaper, said McCain's campaign had left the candidate "nearly unrecognizable." His selection of Alaska Gov. Sarah Palin for running mate was "irresponsible," it said.
"Palin is the most unqualified vice presidential nominee of a major party in living memory," the Times said. "The decision calls into question just what kind of thinking - if that's the appropriate word - would drive the White House in a McCain presidency."
The Times said the U.S. needs a president who displays grace under pressure, is not prone to volatile gestures and understands the legal foundations of American freedom.
"Obama is educated and eloquent, sober and exciting, steady and mature. He represents the nation as it is, and as it aspires to be," the Times said.