YOUNGSTOWN, Ohio — Democrat Barack Obama blamed Republican energy policies for some of the nation's economic woes yesterday as his GOP rival John McCain advocated a large expansion of nuclear power.

Both candidates roamed the economically depressed Rust Belt touting their energy plans as concerns over $4-a-gallon gasoline and job losses have emerged as the presidential campaign's hottest issues.

Obama told an audience in Youngstown, Ohio, that the Bush energy policy, crafted in large part by Vice President Dick Cheney, an ex-oilman, tilted to provide tax breaks and favorable treatment for Big Oil and that McCain would expand oil industry tax breaks by $4 billion.

Obama has proposed an excess profits tax on the oil industry to finance a $1,000-per-family energy rebate to deal with the high cost of gasoline. Outside Detroit, McCain became the first presidential candidate in recent memory to tour a nuclear plant. His energy proposals include building 45 nuclear power plants by 2030 to reduce the nation's reliance on oil imports.

WE'RE NOT BETTER OFF, MCCAIN SAYS

RAPID CITY, S.D. — John McCain conceded in a new television commercial yesterday that "we're worse off than we were four years ago," and said he is the candidate best positioned to usher in an era of change.

"Washington's broken. John McCain knows it," says the commercial.

Just seven months ago, McCain said in a debate that "Americans overall are better off" than eight years ago "because we have had a pretty good prosperous time with low unemployment and low inflation."

OBAMA TAKES LEAD IN AP-IPSOS POLL

WASHINGTON — Solid margins among women, minorities and young voters have powered Barack Obama to a 6-percentage-point lead over John McCain in the presidential race, according to an Associated Press-Ipsos poll released yesterday.

Obama is ahead of his Republican rival 47 percent to 41 percent among registered voters, the poll showed. The survey was taken after Obama had returned from a trip to Middle Eastern and European capitals, and during a week that saw McCain accuse Obama of bringing race into the campaign.

CHENEY MAY SKIP GOP CONVENTION

WASHINGTON —There are doubts about whether Vice President Dick Cheney will attend the GOP convention.

Cheney's press secretary left the question open yesterday, saying Cheney's schedule has not been set for September. Delegates are scheduled to meet in St. Paul, Minn., on Sept. 1-4, to nominate Arizona Sen. John McCain for president.

Separately, at least five Republican senators have decided to skip the convention. Sens. Gordon Smith of Oregon, Elizabeth Dole of North Carolina and Susan Collins of Maine all face tough re-election campaigns. Two others, Wayne Allard of Colorado and Larry Craig of Idaho, are retiring.