As the student-led March for Our Lives movement captured the nation's attention in the weeks after the Parkland shooting, the other side of the gun control debate enjoyed a banner month of its own.

The National Rifle Association's Political Victory Fund raised $2.4 million from March 1 to March 31, the group's first full month of political fundraising since the nation's deadliest high school shooting on Valentine's Day, according to filings submitted to the Federal Elections Commission. The total is $1.5 million more than the organization raised during the same time period in 2017, when it took in $884,000 in donations, and $1.6 million more than it raised in February 2018.

The $2.4 million haul is the most money raised by the NRA's political arm in one month since June 2003, the last month when electronic federal records were readily available. It surpasses the $1.1 million and $1.5 million raised in January and February 2013, the two months after the Sandy Hook school shooting in Newtown, Connecticut.

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Most of the donations, $1.9 million of the $2.4 million total, came from small donors who gave less than $200. The NRA doles out money to political campaigns from the victory fund, but most of its spending is on activity that isn't directly linked with a lawmakers' campaign where the group is not bound by state and federal campaign finance limits. For example, Florida Republican Sen. Marco Rubio received only $9,900 in direct contributions from the NRA during his 2016 U.S. Senate campaign, but his campaign benefited from $3.3 million in outside spending from the NRA to help him defeat Democratic Rep. Patrick Murphy.

In Florida, the NRA has donated to four Republican members of Congress during the 2018 cycle, including Miami Republican Rep. Mario Diaz-Balart, but the four donations are $2,750 or less, a pittance when a competitive congressional campaign typically costs millions. The NRA hasn't donated to candidates at the state level in Florida for years. Instead, the group's political power comes from its thousands of members who are typically a powerful voting bloc in Republican primary elections.

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The NRA did not immediately respond to a request for comment.

Marion Hammer, the NRA's powerful lobbyist in Florida, recently circulated a letter to members titled "It's Time to Name the Betrayers Who Voted For Gun Control," an attack on Republican members of the Florida Legislature who helped to pass a gun bill that raised the age to legally purchase a firearm from 18 to 21, instituted a three-day waiting period for purchasing rifles and shotguns, and banned devices called bump stocks that allow semi-automatic rifles to fire at a higher rate.

"We did NOT support the gratuitous gun control provisions added to the bill by REPUBLICANS," the letter reads. "Republican legislators are responsible for passage of the 'gun control bill.' They lacked the courage to uphold their oath of office and keep their word to constituents who voted for them. They were in total control. They no longer deserve your trust."

The letter went on to call state Sen. Doug Broxson the "lynchpin" who helped pass the bill by one vote in Tallahassee's upper chamber. The Gulf Breeze Republican defended himself in an op-ed after the vote, saying, "When politicians cannot agree in Washington, they pack up and go home, leaving the American people frustrated and angry. Here in Florida, that's just not how we do things."

The NRA spent $31 million to attack Hillary Clinton or support Donald Trump during the 2016 campaign, and the NRA's lobbying arm also spends millions on federal elections, but it does not have to report information on its donors or finances to the FEC. The NRA's Political Victory Fund ended the month with $5.8 million on hand as the 2018 campaign season ramps up.

Gun control groups haven't been able to match the NRA's fundraising. Everytown for Gun Safety's Political Action Fund raised $13,580 in March while former Rep. Gabrielle Giffords' Political Action Committee raised $129,589 in March. Two South Florida lawmakers have received donations from gun control groups this election cycle. Miami Republican Rep. Carlos Curbelo, who introduced a bill to ban bump stocks after the Las Vegas shooting, received $1,000, while Democratic state Rep. David Richardson, who is running for Congress to replace retiring Rep. Ileana Ros-Lehtinen, received $14,108 from gun control groups.

The March for Our Lives group founded after the Parkland shooting has raised $3.5 million since Feb. 18 via the online service GoFundMe, though that money was put toward organizing marches around the country and helping families of the victims.

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