Last Tuesday night, animal welfare activists were poised to celebrate a victory five years in the making.

The next day, the House was set to overwhelmingly approve their measure to elevate the crime of animal fighting to a felony — a provision that gathered 324 co-sponsors in the 109th Congress but was blocked by then-House Judiciary Chairman Jim Sensenbrenner (R-Wis.).

With Democrats in power and a bipartisan roster of 303 co-sponsors, the Humane Society of the United States and others backing the proposal felt assured of swift passage. Then came word that the National Rifle Association was raising last-minute objections.

Though the powerful gun-owners group was silent when the House Judiciary Committee took up the bill last month — and had no position on the dogfights and cockfights the bill addresses — it had some technical concerns. NRA officials worried the language of the measure could open the door for animal rights advocates to forbid legal types of hunting.

“The Humane Society and other extremist animal rights groups, under the guise of saving puppies and kittens, are moving forward with their agenda of banning all sport hunting,” said Chris Cox, the NRA’s top lobbyist.

Cox declined to discuss his group’s tactics, but others close to the issue confirmed the NRA approached the offices of two of its most powerful allies in the Democratic Caucus — Energy and Commerce Chairman John Dingell (Mich.) and Agriculture Chairman Collin Peterson (Minn.) — who agreed to take up the gun lobby’s concerns with House Majority Leader Steny Hoyer (D-Md.).

Hoyer pulled the bill from the calendar, and on Wednesday morning, Judiciary and Agriculture committee staffers hashed out a compromise that appeased both the NRA and the Humane Society. The measure is expected to come up for a vote early this week.

The Humane Society claimed victory —“We’re glad the delay was short and we’re moving forward,” said Michael Markarian, a lobbyist for the group — but clearly was rattled. Markarian speculated the NRA intervened simply to show they could. “Our feeling was the NRA was trying to meddle because they don’t like the Humane Society.”

So far in the 110th Congress, gun control advocates have not fared much better against their old foe. After more than a decade of playing defense, and losing, under Republican control, groups such as the Brady Campaign to Prevent Gun Violence woke up the morning after Election Day thinking a new era had begun.

“In this election, the gun issue was in play, gun violence prevention groups won while the gun pushers lost, and there is now a shift in momentum on the issue of common sense gun restrictions,” Paul Helmke, president of the Brady Campaign, said in a statement after the November elections.

Any lingering doubt about the gun lobby’s continued juice under Democratic rule was laid to rest Thursday. House Republicans, maneuvering to derail a bill to grant Congressional voting rights to the District of Columbia, inserted a provision in their alternative measure that would dramatically scale back the city’s gun restrictions.

But nervous that conservative members of their Caucus who favor gun rights could switch sides and hand the Republicans a victory, House Democratic leaders pulled the bill from consideration — and Republicans gloated. “Fearing that many in their party would support Second Amendment rights for District residents, the Democratic Leadership shamefully exploited a rule to kill debate and postpone the vote indefinitely,” House Minority Leader John Boehner (R-Ohio) said in a statement.

Though the NRA has pushed in the past to roll back the district’s gun restrictions, Cox said his group had no hand in the effort on the voting rights bill. Nevertheless, he said its fate testifies to the potency of the issue. “What you’ve seen is the political reality that the Second Amendment is a major political force, not only on Election Day, but throughout the legislative process,” he said.

A House Democratic aide dismissed that take, calling the Republican gambit a political stunt aimed at sinking the bill. He said it had nothing to do with gun rights.

Peter Hamm, spokesman for the Brady Campaign, similarly took a different view. “I would say they’ve lost an enormous amount of their political power,” he said of the NRA. He added that 109 House candidates and 18 Senate candidates who either were endorsed by the NRA or were A-rated were defeated in 2006.

To the extent it exists, the NRA’s traction in a Democratic Congress results from a combination of factors. In addition to a handful of well-placed friends in the party, the NRA is looking to a majority of freshman Democrats — many of whose rural Members campaigned on a pro-gun platform — to help advance its agenda and block new regulations on the gun industry and owners.

It also is hoping to benefit from a calculation Democratic strategists have made in recent cycles that a focus on certain social policy issues — a triumvirate commonly tagged “God, guns and gays” — only damages the party politically.

Indeed, candidates appeared to steer clear of gun control issues nearly across the board in the last campaign. As a result, pressure groups on both sides of the debate drastically scaled back their activity, decreasing their political giving by 45 percent, according to an analysis by the Center for Responsive Politics. That marked the biggest drop-off of all industries and interests in the cycle.

The NRA handed out nearly $1 million during the 109th Congress, with 85.5 percent going to the GOP, according to CQ PoliticalMoneyLine. And the group fared well under Republican control. In the past Congress, it scored two major wins, successfully pushing liability protection for gun makers and, in the wake of Hurricane Katrina, a measure to ban the confiscation of firearms after an emergency.

Cox acknowledged that the Democratic leadership “has been traditionally hostile to our positions.”

“Yet they seem to recognize the fact that a large part of their Caucus is not only not hostile but is supportive,” he said. The group’s political giving has started shifting, if only slightly. For the first two months of the year, it has handed out $77,500, with 75.6 percent going to Republicans, according to FEC records.

Cox said the group will stay on offense, with an agenda that includes keeping law enforcement records on gun crime sealed, increasing support for gun crime prosecutions and rolling back restrictions in the district.

Hamm, meanwhile, said his group, buoyed by the election returns, is pursuing a number of goals: closing the gun show loophole, boosting funding to the Bureau of Alcohol, Tobacco and Firearms and opening federal books on crime gun data.

“But we’re realists,” he said. “We know that undoing some of the reversals of the last several years is going to take some time.”