Congress has dodged a government shutdown, agreeing to a $1 trillion spending bill that features a variety of rare compromises. Both Democrats and Republicans won some concessions, and it's too early to say who came out on top. But there's one issue where the GOP seems to have won lights-out: the battle of the bulb.

House Republicans have become livid in recent months about the Energy Department's updated efficiency rules for light bulbs, which were signed by President George W. Bush in 2007 and scheduled to take effect Jan. 1. The standards are meant to help the U.S. use less electricity, requiring that traditional incandescent bulbs become 30 percent more energy-efficient by 2012.

But under the new omnibus spending bill, Republicans have blocked the light-bulb standards by prohibiting the Energy Department from using federal funds to implement them. The rules can technically still take effect next month, but the GOP rider will prevent the U.S. from enforcing them through Sept. 30, Politico reports.

Critics have cast the standards as a "light bulb ban," suggesting they would outlaw incandescent bulbs in favor of compact fluorescent lamps, or CFLs. But supporters point out that no specific type of bulb would be outlawed; incandescent bulbs could still be sold under the new rules, as long as they're 30 percent more efficient than older models. CFLs and other energy-efficient bulbs are costlier to buy up-front, but they save money in the long run: A typical CFL saves $30 over its lifespan, according to the U.S. Energy Star program, and pays for itself in about six months.

CFLs do contain small amounts of mercury, but it's only a risk if the bulb breaks. This can make recycling CFLs difficult, although proponents point out that coal-fired power plants release mercury directly into the environment. Since traditional bulbs need more electricity, they argue, CFLs actually have a smaller "mercury footprint."

The pushback against the efficiency rules was led by conservative talk-radio hosts like Rush Limbaugh, as well as by Rep. Michele Bachmann, R-Minn., who's running for president. ("President Bachmann will allow you to buy any light bulb you want," she said earlier this year.) And while Republicans have recently abandoned several other environmental riders in the spirit of progress — including major cuts to the EPA — many felt too strongly about the light-bulb issue to simply let it go.

"Speaker [John] Boehner to Chairman [Fred] Upton to Chairman [Hal] Rogers, they all strongly support keeping it in," says Rep. Joe Barton, R-Texas, who served on the House Energy and Commerce Committee in 2007 when the energy law was approved. "And it's a personal commitment because of their philosophy."

According to Rep. Jan Schakowsky, D-Ill., the GOP bulb block is "just another poke in the eye." Rep. Peter Welch, D-Vt., attributes it to "the power of Michele Bachmann and the presidential campaign." And on Twitter, Sen. Jeff Bingaman, D-N.M., wrote, "I strongly oppose that language. I hope it's deleted from any final bill that we pass."

A spokeswoman for the House Appropriations Committee, however, says the GOP's anti-efficiency provision remains in the final version of the bill. "There is no change in this language from the version that was posted last night," she tells the Hill.

On Thursday, some lawmakers from both sides of the aisle expressed exhaustion, even apathy, about the measure. "Is it a must-have for me? No," said Sen. Lisa Murkowski, R-Alaska. "That was not something that I got focused on or took up as an initiative." As Rep. Jim Moran, D-Va., groused, "It's not even worth talking about. It's something that can always be worked out."