Critics labeled it a stunt when Congressman Sam Graves and other Republicans kept the U.S. House in motion during the August recess calling for a vote on expanded energy exploration.

Now, it appears the exercise might have had an impact, if only a measured one.

The Democratic majority in the House opted to let a moratorium on oil drilling along the outer continental shelf expire on Tuesday. The coastal-drilling moratorium has been in place for more than a quarter-century.

Though a bargaining chip in negotiations on a larger stopgap spending, and a moratorium that might be reinstated depending on the outcome of November’s presidential election, the expiration was seen as a victory by Mr. Graves.

“This is the biggest step forward for our country’s energy independence in the last 25 years,” the Northwest Missouri Republican said.

Mr. Graves went to Washington on Aug. 20 as part of a revolving group of Republican representatives who occupied the quiet House chamber and advocated a vote on expanded drilling.

With high gas prices across the United States, public sentiment ran toward the broader exploration, and Republicans pushed it at their national convention with “drill, baby, drill” chants.

The drilling issue became a campaign hot-button in Mr. Graves’ re-election bid with claims that his opponent, Democrat Kay Barnes, favored the position of House Speaker Nancy Pelosi in opposing the exploration.

The Barnes campaign insists the challenger “continues to support alternative energy and increased domestic drilling.”

On Friday, Mr. Graves voted against the Renewable Energy and Job Creation Act, which passed in the House by a 257 to 166 margin. His continued opposition to such legislation has centered on the tax provisions included.

The Barnes campaign counters that Mr. Graves took campaign money from big oil companies and looked past home-district interests in voting against the energy legislation.

Ken Newton can be reached at kenn@npgco.com.