The Senate is set to vote on four gun control measures Monday evening — and none of them is expected to pass.

Getting these votes scheduled was the singular goal of a 15-hour talking marathon Senate Democrats mounted on the Senate floor Wednesday. But because the outcome of the votes is already a foregone conclusion, some senators are wondering out loud: "What's the point?"

"This is unfortunately about politics on Monday night, not about finding a solution that will work for our country," said Republican Bob Corker of Tennessee.

What concerns Corker, especially, are two dueling approaches on how to handle gun purchasers who appear on the federal terrorist watchlists. The two proposals are up for a re-vote — they both failed in the Senate last December. Corker thinks his colleagues are still confused about what the terrorist watch database actually is. "Not three people in the United States Senate," he said, can explain the differences between the various lists the government maintains to track suspected terrorists.

"The fact that we're going to vote on this Monday is an intentional way to keep this as an issue. It's not a way to solve this problem. And I'm disappointed that that is what is happening," Corker said. "This is something that deserves real hearings, real discussions about how these lists are put together and how you get off these lists."

The terrorist watchlist measure Democrats are pushing was crafted by Democrat Dianne Feinstein of California. It would give the Justice Department the power to stop anyone from purchasing a gun if that person has been on the federal terrorist watchlists sometime in the past five years. Under her bill, the government could also halt a gun purchase if the FBI has a reasonable belief that the individual will use the firearm to commit terrorism. The White House backs Feinstein's measure.

Republican John Cornyn of Texas is pushing a competing proposal. Under his bill, the Justice Department could delay a gun purchase if the buyer has appeared on a terrorist watchlist in the past five years, but in order to permanently block the purchase, the government has three business days to get in front of a judge and show probable cause. In other words, federal investigators must — within three days — amass enough evidence amounting to probable cause to show the person is a known or suspected terrorist. Republicans say this requirement ensures greater due process for individuals placed on the terrorist watchlists before they potentially lose their Second Amendment rights.

But many Democrats say Cornyn's proposal would do little to stop suspected terrorists from buying firearms.

"Do you know what the Republican proposal — Cornyn's proposal — says?" asked Chuck Schumer of New York at a press conference Thursday. "It says that if the FBI thinks you're a terrorist, they have three days to go to court and get an adjudication, and, if not, you can get a gun. Every terrorist will get a gun. If the FBI had that evidence, they would have arrested the person to begin with."

Feinstein and Cornyn began talks to see whether there was a middle ground between their proposals, but those negotiations quickly fizzled this week.

"I got word that he had sent it to the NRA, and that was sort of a clue," Feinstein explained. "And I called, and I didn't get a call back."

Even if the outcome of Monday's votes surprises no one, some Senate Democrats say they're convinced their 15-hour talk-a-thon on the Senate floor this week has shifted ground and prompted colleagues on the other side of the aisle to brainstorm workable solutions.

Republican Susan Collins of Maine, for example, is pushing a measure that would flag authorities if someone on either the no-fly list or the Secondary Security Screening Selection list tries to buy a gun. Collins says the broader database that Feinstein's and Cornyn's measures use scoops up too many people — sometimes by mistake. The government can stop someone on these smaller, more scrutinized lists from buying a gun, but that person can appeal the decision to an appellate court.

"I don't think any of this would have happened had we not stood on the floor yesterday for 15 hours and demanded that we move forward," said Democrat Chris Murphy, who became one of the leading gun control advocates in the Senate after the shootings in Newtown, Conn., and who led Wednesday's talk-a-thon. "If we didn't have a vote scheduled on the Feinstein proposal, I don't think we would have people scurrying around trying to find potential compromises."

Murphy said 10,000 people "from every state in the nation" called his office on Wednesday offering their support. So even if Monday's votes don't change anything, Murphy says, the conversation within the Senate won't be over.

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