The National Rifle Association, the nation’s largest gun lobbying group, is targeting a handful of Democrats in close Senate races with one of the most provocative — if not downright scary — ads of the campaign season.

Let’s set the scene : A young mother puts to bed her infant child and receives a text, presumably from her husband, letting her know his plane landed.

"Love you. Good night," she texts back.

Suddenly, an ominous shadow is outside a window and a figure busts into the front door. Cut to a scene with police tape outside the home, suggesting tragedy.

"It happens like that," a narrator says. "The police can’t get there in time. How you defend yourself is up to you. It’s your choice. But Mary Landrieu voted to take away your gun rights."

Replace Sen. Mary Landrieu, D-La., with Sen. Mark Udall, D-Colo., and you get the ad running in Colorado.

How do we get from a vote in Congress to an intruder barreling through a poor woman’s front door? It’s far from a straight line.

The NRA’s first justification

When the Washington Post Fact Checker looked at this question, NRA spokesman Andrew Arulanandam pegged Landrieu’s vote "to take away your gun rights" to her support of the Toomey-Manchin proposal (named after its sponsors, Sen. Pat Toomey, R-Pa., and Joe Manchin, D-W.Va.).

That proposal, which failed 54 to 46 in April 2013, did not ban the sale of any firearms. Its most significant provision would have expanded federal background checks already in place to firearm purchases made at gun shows and over the Internet. You could still buy a weapon from a family member or friend without a background check.

The Fact Checker concluded that it’s hard to envision a situation in which Toomey-Manchin would have prevented a woman from being able to defend herself against an intruder. Assuming the woman in the ad was legally eligible to purchase a firearm (meaning she doesn’t have a criminal record ), she would not have any trouble owning a gun in her home — even if Toomey-Manchin passed.

The Fact Checker gave the claim Four Pinocchios, its harshest rating.

The NRA’s second justification

By the time PolitiFact inquired, the NRA offered different evidence as support for its claim. The group told PolitiFact that its claim stems from Landrieu’s vote to confirm Justice Sonia Sotomayor to the Supreme Court in 2009, a pick the NRA opposed.

"Landrieu voted to confirm at least one anti-gun and anti-self defense (Supreme Court) justice," said NRA spokesman Arulanandam. "Anti-self defense is life or death."

During Sotomayor’s nomination proceedings, her past ruling on a Second Amendment issue became a talking point for Republicans who were critical of President Barack Obama’s choice.

While on the U.S. Court of Appeals for the Second District, Sotomayor was part of a three-member panel that reviewed a lower court ruling in Maloney vs. Cuomo . At issue was whether New York could ban the chuka stick (commonly called nunchucks, a weapon with two sticks connected by a chain or rope).

Sotomayor was part of a majority opinion that ruled the New York statute legal. The Second Amendment applies to federal laws but not state laws, they wrote, citing an 1886 Supreme Court decision.

During her confirmation testimony, Sotomayor reasoned that the Supreme Court had not yet ruled on whether its decision in Heller vs. District of Columbia — which overturned the federal capital’s handgun ban — applied to all cities and states. So, Sotomayor said, she was applying the precedent as it was understood at that point.

Several Republican senators cited this case as reason to vote against Sotomayor’s nomination.

(Worth noting, Landrieu actually supported the court’s decision in Heller to overturn the D.C. handgun ban and signed onto a letter from Sen. Kay Hutchison, R-Texas, to codify the Supreme Court’s ruling.)

The Supreme Court eventually ruled, by a 5-4 margin in 2010, to strike down Chicago’s ban against owning a handgun in the home. This effectively applied the Heller ruling to all local governments. Sotomayor, by then on the Supreme Court, signed on to a minority opinion that argued the Second Amendment did not prohibit local governments from regulating firearms or banning certain weapons in the home.

No other major gun issues have come before the Supreme Court during Sotomayor’s time. In fact, it has turned down requests to review the right to have a handgun outside the home, said Amy Howe, editor of the popular Supreme Court analysis website SCOTUSblog.

Problems with the second justification

So how convincing is the Sotomayor argument? It has some considerable holes.

For starters, it’s a slippery slope to claim that a vote for a Supreme Court justice is a vote "to take away your gun rights."

To use the same logic, was a vote to confirm President George W. Bush’s nomination of John Roberts also a vote for the Affordable Care Act just because he ruled to uphold the individual mandate? Was a vote for Justice Anthony Kennedy — the justice appointed by President Ronald Reagan who became the swing vote in the case that effectively ended California’s same-sex marriage ban — a vote to legalize same-sex marriage?

In other words, no one can tell in advance how justices will eventually vote on issues that come before the court. Justices appointed by Republicans can surprise and take what would be considered the liberal position in a case, and vice versa.

We will also note that Sens. Lindsey Graham , R-S.C., and Lamar Alexander , R-Tenn., joined seven of their Republicans to confirm Sotomayor’s nomination. Yet the NRA gave them each an A- rating for their votes on gun issues and endorsed them for reelection this year. So this is either selective memory or the NRA applying its own logic differently to candidates.

As for Landrieu, her campaign said she has supported pro-gun measures over the years, including a proposal that requires states to recognize concealed carry permits issued by other states. She also voted against an assault weapons ban supported by the White House in the aftermath of the Sandy Hook Elementary School shooting. The NRA also opposed the measure.

Our ruling

The NRA ad claims, "Mary Landrieu voted to take away your gun rights." This is quite a leap in logic.

After initially staking its claim to a background check bill that didn’t pass Congress — nor did it "take away your gun rights," leaving women defenseless in their homes — the group now pins its claim on Landrieu’s vote to confirm Sotomayor to the Supreme Court. But that’s questionable, since there is no way to know in advance how a justice will vote. And the NRA has endorsed two other senators, Graham and Alexander, who cast exactly the same vote. Meanwhile, on the other major gun vote of this term, a key assault-weapons ban, Landrieu voted the NRA’s position.

Given all this, to run an ad as scary as this one can only be described as fear mongering. We rate the claim Pants on Fire.