Just days after President Trump was inaugurated, the GOP-controlled Congress agreed on several Obama-era rules it would seek to repeal using a law that allows it to overturn recently completed regulations. The methane rule was the very last up to bat, and the Senate didn't take it up until the last-minute.

The delay allowed groups like the Environmental Defense Fund and Taxpayers for Common Sense to keep pressuring moderate members from both parties on the issue from different angles: climate change and the environment (methane is a potent greenhouse gas) and taxpayer money (the rule requires companies to capture instead of inadvertently emit methane, the primary component of gas, from wells on federal lands).

Time allowed a group of Republican senators from states with big ethanol interests to conjure up a demand that they would only vote yes if they got a policy backing ethanol in return. This muddied the waters in the whip count, according to people familiar with the effort.

Time allowed for coincidental occurrences, including:

• Some stakeholders speculated whether Sen. John McCain (R., Ariz.), voted against the measure because he was upset about a separate nominee process. McCain said in a statement he voted against it because he thinks the government should regulate methane emissions.
• Others speculated whether there was any collateral impact from the firing of FBI director James Comey. "It's not that I didn't think it last night," said Ryan Alexander, president of the taxpayers group. "I don't think that was the motivation for the three Republicans who voted with us."