DENVER — For a man whose life could change forever next week if chosen as the Republican vice presidential nominee, Mitt Romney was relaxed, upbeat and in full GOP attack mode Tuesday as he invaded a town full of Democrats.

He traveled to Denver, he said, to get "beyond the glitz and the glitter" of the Democratic National Convention there and "focus on the facts."

And the main fact, he said, is that Barack Obama may be "a fine person. But he is not ready to be president." He said John McCain is ready, and the nation and world will be vastly different depending on who is elected. At a crowded press conference at McCain's Colorado headquarters, reporters asked Romney and Rep. Eric Canton, R-Va., both considered leading contenders to become McCain's running mate, if they had any news about that vice presidential pick. They both laughed — and then quickly ended the half-hour press conference.

Romney shot with both barrels at Obama at the press conference, saying such things as, "He voted 94 times to raise taxes," "He's wrong on spending," "He's wrong on trade" and "You don't grow the economy by raising taxes and limiting trade."

At an earlier private gathering with some reporters, he also praised McCain as strongly as he attacked Obama.

Among other things, Romney, looking thin and tan, said Obama made a serious tactical error when he made fun of McCain not immediately listing the number of homes he and his wife own.

"It was wrong, offensive. John McCain is a true-blooded hero. All Americans see this as the politics of envy, and it will not be successful in the final analysis," Romney said.

All Obama did in that political flare-up was point to his own housing record — "Obama got a special deal from a convicted felon" — who helped the Obamas buy a lot next to their new house.

"Every effort to portray John McCain as someone who doesn't connect with the American people will fall extraordinarily short, just as the efforts to say he is a continuation of George Bush," he said.

"The American people recognize that is total baloney. They know that John McCain was a maverick in the Senate" who voted against Bush's wishes "on major" issues of the day.

Asked how many homes Romney owns (he is worth hundreds of millions of dollars) Romney said: "Four, one less than John Kerry," the 2004 Democratic presidential nominee. One of Romney's homes, by the way, is in Deer Valley, Utah.

As has been the case in recent weeks, Romney declined to talk about McCain's vice presidential pick, even refusing to say if the McCain camp had vetted Romney for any problems should he be asked to join the ticket.