Updated

President Bush (search), harshly criticized by Democrats during their four-day convention, opens a new phase of his re-election campaign Friday by promising better times and fresh ideas for America. "We have turned the corner, and we are not turning back," he says.

Beginning a two-day swing through four presidential battlegrounds, Bush planned to take a subtle slap at Democratic rival John Kerry (search). "When it comes to choosing a president, results matter," Bush said in excerpts of his new stump speech obtained by The Associated Press.

Bush planned to travel by bus and plane through Missouri, Michigan, Ohio and Pennsylvania as Kerry departs Friday from Boston and his party's convention for a two-week cross-country trip by bus, train and boat and plane.

Two presidential advisers, speaking on condition of anonymity, said Bush would offer broad outlines of his re-election agenda on what Republicans are billing as the "Heart and Soul of America" tour. Then, for the next two weeks, he will focus on his ideas for helping Americans adjust to the changing economy: increasing home ownership, overhauling Social Security (search) and letting workers opt for time off rather than overtime pay -- an issue that has riled unions, Democrats and some moderate Republicans.

None of these ideas are new, but the officials said Bush will outline fresh initiatives. In mid-August, the nation's fight against terrorism will become the campaign theme, they said.

The White House hopes to cast Bush as a can-do leader, and convince voters that Kerry has not earned the right to replace the wartime incumbent. In his new stump speech, Bush says results are what count in education, health care and other areas -- but no more so than in filling the highest office in the land. Aides said that was a suggestion that Kerry has not produced much in his two decades in the Senate.

A new Bush ad campaign will stress similar themes, the aides said.

Bush was heading to Washington on Thursday after a weeklong vacation at his Texas ranch. He kept a low profile while Democrats rallied behind Kerry, watching some of their Boston convention on television, his spokesman said.

The president will spend less than 12 hours in the White House before heading to Missouri at dawn Friday.

Political analysts say the state is leaning toward Bush, and John Kerry's campaign has reduced its advertising campaign there after polls showed him 4 to 6 percentage points behind the president.

With the visit Friday to Springfield, Bush wants to exploit the fact that the state is trending Republican, said George Connor, associate professor of political science at Southwest Missouri State University. Both houses of the state legislature went Republican in 2002.

Bush also is trying to reassure voters about his handling of the war in Iraq.

"Every few days in the papers somebody's son from the Ozarks dies in Iraq or Afghanistan, which has led to an undercurrent of concern among the electorate," Connor said.

Bush won Missouri in 2000 with 50 percent of the vote to Al Gore's 47 percent. Friday will be the president's 20th trip to the state.

Later in the day, he campaigns in Grand Rapids, Mich. -- his third trip to the state in 17 days and his 17th as president. Bush lost Michigan in the last election, and most polls show the state tied or leaning toward Kerry.

On Saturday, Bush will campaign by bus through eastern Ohio, his second bus tour in the state in three months. He will wrap up two days of campaigning with a rally in Pittsburgh, just hours after Kerry speaks in a nearby suburb.

While Bush followed tradition by lying low during his opponent's convention, Vice President Dick Cheney campaigned through it, criticizing the Democratic ticket. Cheney planned to campaign Friday in Oregon and Washington while Laura Bush headlined a fund-raiser for Republican Senate candidate Richard Burr in North Carolina.