Republican presidential candidate John McCain will tell an economically depressed city in Ohio on Tuesday that it can rebound just like his once struggling campaign came back from the dead.

"Sometimes you get a second chance, and opportunity turns back your way," McCain will say in Youngstown, Ohio. "And when it does, we are stronger and readier because of all that we had to overcome."

McCain's campaign was in trouble last summer, short of cash and given up for dead by many political pundits who were waiting for him to withdraw from the race.

The Arizona senator mounted a comeback in New Hampshire and outlasted his rivals to clinch his party's presidential nomination, while Democrats Barack Obama and Hillary Clinton are still fighting for the right to face McCain in the November election.

As Democrats vote in Pennsylvania on Tuesday, McCain will point out his good fortune of being "in the unfamiliar position of facing no opposition within my own party."

"As you might recall, it was a different story last year, when I could claim the unqualified support of (his wife) Cindy and my mother - and Mom was starting to keep her options open," he will say, according to excerpts released by his campaign for delivery at Youngstown State University.

McCain is trying this week to appeal to moderate voters by visiting places left behind by America's economic engine. After touring Alabama's rural "Black Belt", he will advocate quality job retraining programs for unemployed steel workers and others in Ohio.

Youngstown is in a region often called the "Rust Belt" because it was a centre of steel production that fell on hard times when the industry declined in the 1970s.

McCain will say there is hope in "green" technology as well as new software and technology companies that have located in Youngstown.

"It won't be easy, and, as you know better than I do, it won't happen overnight. But dramatic change can happen, in this great city and others like it," he will say.