INDIANAPOLIS – Hillary Clinton won Pennsylvania by feeling the pain of blue-collar voters. Now she's trying for a repeat here in Indiana, playing on voter frustration over high gas prices.

Mrs. Clinton addressed factory workers earlier this week at this city's Miller Veneers plant, which produces hardwood veneers. She railed against high pump prices and the "record" profits of oil companies, then introduced her five-point plan, which consists of equal parts fulminating at Big Oil and OPEC and waiving the federal gas...