U.S. Sens. Pat Toomey, R-Pa., and Joe Manchin, D-W.Va., set the table for two weeks or so of upcoming gun control legislation debate by reaching an agreement to support expanded criminal background checks on commercial gun sales.

Broader measures, like banning some assault weapons and limiting the number of bullets in ammunition clips, are unlikely to pass even the Democratic-controlled U.S. Senate, but the background check issue and some mental health measures still have political viability.

Toomey, a staunch conservative, argued that improving background checks is not even gun control.

“It’s common sense. If you pass a criminal background check, you get to buy a gun. No problem,” Toomey said. “It’s the people who fail a criminal or mental health background who we don’t want to have a gun.”

The Toomey-Manchin legislation would expand criminal background checks to cover all commercial and online gun sales and to end the so-called gun show “loophole” of buying guns at events without proper checks. That proposal would exempt background checks on unadvertised private transfers of weapons, including among family members.

The legislation does not create any kind of federal gun registry.

But even the idea of expanding background checks could die a relatively quick death in the GOP-controlled House and most of the Louisiana congressional delegation already opposes it. U.S. Sen. David Vitter, R-La., voted against just having debate on the issue.

Most of the opposing arguments focus on the need to better enforce existing laws and to avoid making it harder for “law-abiding citizens” to buy guns.

“The long and the short of it is I’m going to oppose any law that makes it more difficult for law-abiding citizens to get guns to protect themselves,” said U.S. Rep. Steve Scalise, R-Jefferson, who added that expanding background checks falls into that category.

Scalise said the Obama administration should instead be doing much more to prosecute those with criminal backgrounds who try and fail to purchase firearms.

U.S. Rep. Charles Boustany, R-Lafayette, argued that the gun-show loophole is overhyped and that the focus should be on preventing legally purchased weapons from eventually falling into the hands of criminals.

“I think anything coming over from the Senate is going to have a hard time in the House,” Boustany said. “I take the Second Amendment very seriously.”

U.S. Rep. Rodney Alexander, R-Quitman, said attention is necessary on the societal issues, like drug abuse, which lead to shootings.

“I just think until we address the real problem — and that’s the cause of gun violence — then I don’t think I can support it just to say, ‘It looks good. We did something,’” Alexander said.

U.S. Rep. Cedric Richmond, D-New Orleans, who is the only member of the delegation to openly support more gun control, has a very different take. He called it “common sense” to improve criminal background checks, arguing that many Republicans are only concerned about losing their support from the National Rifle Association.

“I think our Republicans defer their deliberative thought process to the NRA,” Richmond said. “That’s a true disservice. If you look at the background check bill, that is not an infringement of the Second Amendment.”

The only members of the delegation not to weigh in definitively on background checks are Sen. Mary Landrieu, D-La., and Rep. Bill Cassidy, R-Baton Rouge, who is challenging Landrieu for her Senate seat next year.

Cassidy, who opposes any weapons bans or ammunition limits, said he is unsure about the background check expansion because he needs to review the bill’s language first. “I think that everyone wants to do something effective to keep criminals from getting guns,” Cassidy said.

If legislation does that without infringing on the Second Amendment, Cassidy said, “then it’s something I’ll look at.”

Any gun control votes likely will be used against Landrieu in her re-election bid next year. She said she would not say yet how she will vote without reviewing the details of the bills and proposed amendments.

“Gun violence in America is high, shamefully high. Our state is one of the highest, of course,” Landrieu said. “It’s not just gun violence in schools; it’s gun violence on our streets. On the other hand, I feel strongly that people should have access to rifles for hunting and outdoor sports and recreation, which is a time-honored sport in Louisiana.”

Landrieu in the past has supported extending background checks to gun shows. Landrieu voted against reinstating the assault weapons ban in 2004, arguing that it did not do enough to prevent violence. But she said she backed the ban when she first ran for the Senate in 1996.

Jordan Blum is chief of The Advocate’s Washington bureau. His email address is jblum@theadvocate.com.