House Democrats, some chanting “drill, drill,” embraced a plan to open the door for more oil and natural-gas exploration along the entire U.S. coastline, in a shift showing the power of the energy issue in this election.

The Democrats’ turnabout marks a victory for the oil industry and Republicans, who have seized on the drilling issue in recent months. With gasoline prices still high at the pump, polls show Americans in favor of expanded oil production at home, and Republican presidential candidate Sen. John McCain has made the issue central to his campaign, as have congressional Republicans.

Even Sen. Barack Obama, the Democratic Party’s presidential standard-bearer, has endorsed expanded drilling as part of a comprehensive bill boosting conservation and renewable energy, such as wind and solar power.

The decision to push the more aggressive plan in part reflects the leverage the White House has to shape the agenda. Bush aides have signaled that the president might not support a spending bill needed to finance basic government operations beyond Sept. 30 unless Democrats allow a longstanding moratorium on offshore drilling to expire. It isn’t clear if the new House bill will ever become law. But given the sensitivity of the issue — and the White House’s leverage — the measure unveiled Wednesday can be seen as an opening bid in negotiations over details of the end-of-year spending bill.

The Democratic bill is designed to boost production and conservation, while putting the oil industry and its Republican allies in an uncomfortable position: choosing between much-coveted drilling rights in unexplored areas along the coast or the guaranteed benefit of tax breaks, which the bill would scale back under a provision that extends new tax preferences in support of renewable energy.