UPDATE 2-Clinton says Obama voted for oil firm tax breaks

(Adds background, Obama repudiation of pastor)

By Jon Hurdle

PITTSBURGH, March 14 (Reuters) - Sen. Hillary Clinton on Friday renewed her attack on oil company profits and accused Sen. Barack Obama, her rival for the Democratic presidential nomination, of supporting tax breaks for oil companies.

Speaking at a campaign rally for about 2,000 supporters in Pittsburgh, Pennsylvania, Clinton said both Obama and Republican presidential candidate Sen. John McCain had voted for a bill to cut oil company taxes.

"They voted yes to more giveaways to the oil companies," she said during a 40-minute speech.

Citing Exxon Mobil Corp's latest annual profit of $40 billion, Clinton said that as president, she would require oil companies to invest in alternative forms of energy or else be subject to a windfall profits tax.

She pledged to set up a $50 billion Strategic Energy Fund to develop non-fossil fuel energy sources, and would pay for it by ending tax subsidies that she said have been enjoyed by oil companies during the administration of Republican President George W. Bush.

Clinton and Obama are locked in a bitter Democratic fight in the state-by-state contests to determine who will face McCain in November's presidential election. Pennsylvania's April 22 contest has the biggest single-state haul of nominating delegates - 158 - remaining in the race.

The new U.S. administration, Clinton said, should place a high priority on the search for clean, renewable sources of energy such as wind and solar.