At a joint appearance at the National Steinbeck Center, the men pronounced their fierce GOP primary battles a mere "family squabble." They said they were united in their desire for Mr. Bush and running mate Dick Cheney to defeat Democrats Al Gore and Joe Lieberman in November.
Mr. Bush and the Arizona senator began a three-day campaign swing together through California, Oregon and Washington in hopes of wooing the sort of moderate and independent voters who backed Mr. McCain in the GOP primaries.
"John is going to help a lot in those states," Mr. Bush told reporters after addressing 75 invited guests at the museum honoring The Grapes of Wrath author John Steinbeck, who was born in Salinas. "Those are states where in the past election cycle people said, 'Republicans don't even have a chance.' Now we not only have a chance, we're going to do well."
Mr. McCain, who introduced Mr. Bush in Salinas, praised the Texas governor as the best-qualified candidate for president and urged independents to consider voting for him. Still, there were signs that the senator was a loyal GOP soldier rather than a true convert to the Bush cause.
An empty seat separated Mr. Bush and his wife, Laura, from Mr. McCain, who took a subtle jab at the nominee in his introductory remarks.
"This good and decent man with his wonderful wife â€“ the brains of the outfit â€“ is going to lead this nation," Mr. McCain said. "I'm proud to be part of this crusade."
A few months ago, Mr. McCain was on his own crusade against Mr. Bush. The two Republicans waged a bruising primary fight in which Mr. McCain once said of Mr. Bush, "If he's a reformer, I'm an astronaut."
In his campaign, Mr. McCain vowed to vastly reduce the influence of money in politics and criticized Mr. Bush for not going far enough toward that goal. He also said Mr. Bush's proposed $1.3 trillion tax cut over the next 10 years was too large, arguing that some of the money should be used to shore up Social Security and pay down the national debt.
Thursday, Mr. McCain acknowledged to reporters that he and Mr. Bush still have their differences. Mr. McCain said he shares some views held by Mr. Lieberman, a senator from Connecticut, on campaign finance issues, whereas he and Mr. Bush are still having "discussions" on the subject. And the two still disagree on the size of Mr. Bush's proposed tax cut, Mr. McCain said.
Mr. McCain, however, stressed that he and Mr. Bush share the core Republican philosophy of fiscal conservatism, individual liberty and placing power in the hands of people rather than bureaucracies. And he said he felt far more confident about Mr. Bush now than at the end of the primary season, praising the message of inclusion and diversity that the governor has injected into his campaign and, more generally, into the Republican Party.
"Yes, we had our differences, but differences are healthy within a party," Mr. McCain said. "That's what primaries are all about. But he and I are united to move forward. I will help however I can with the campaign."
Mr. Bush said that he was proud to have Mr. McCain traveling with him and that there were no lingering hard feelings from the primary contests.
"Primaries are family squabbles," Mr. Bush said. "It was a tough campaign, and I'm a better candidate as a result of John entering the race. We were friends before, and we're friends now."
In remarks at the Steinbeck Center and later at a rally in Salinas, Mr. Bush touted his record on moving people off welfare and into jobs.
Later, Mr. Bush and Mr. McCain boarded a train for the Northern California town of Lodi. As Mr. Bush addressed several thousand supporters late Thursday, a man holding an anti-Bush sign was escorted away by a Bush aide.
Eric Armstrong's sign read, "Bush Equals Pollution, Bush Wrong for Our Environment."
When questioned why a silent protester would be escorted away, Bush spokeswoman Karen Hughes said the area in front of the stage was for VIPs only, rented by the California Republican Party for $1,500.
"In areas where we've invited guests, we don't allow people with negative signs to come in," she said.
Later on Thursday, Mr. Bush and Mr. McCain attended a $1,000-a-plate fund-raiser in Stockton for the California Republican Party at the home of San Diego Chargers owner Alex Spanos.
Although all of Mr. Bush's California stops Thursday were in counties carried by Democrat Bill Clinton in the last election, Bush aides said their analysis shows that about 25 percent of voters in the region can be considered up for grabs. California, which offers 54 of the 270 electoral votes needed to win, has been a Democratic stronghold in recent elections.
Mr. McCain said he would do what he could. "All I can do, really, is ask independents to take a look at Governor Bush," he said. "Obviously, independents are independent because they're independent."