Liberal organization Run for Something co-founder Amanda Litman said her organization has seen a 2.5-fold increase in people signing up saying they want to run for office since taking out a full-page ad in a Florida newspaper about state legislators who are supported by the National Rifle Association and are running unopposed. Litman said on CBSN that there are 24 state lawmakers in Florida who are running unopposed in the November election who have an A or A-plus rating from the NRA.

"If they don't have people running against them, there is nobody who can hold their feet to the fire for the positions they're taking that put our kids in danger," Litman said.

The ad ran in the South Florida Sun-Sentintel on Sunday and it will run again on Wednesday.

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Since the Feb. 14 shooting in Parkland, Florida, that killed 17 students and wounded 15 others, students from the high school and their community have been fighting for tougher gun control laws and have taken on the NRA. Students traveled to the state capital, Tallahassee, to rally for change in the state's gun laws on Feb. 21.

At a CNN Town Hall on Feb. 22, student Cameron Kasky asked Republican Sen. Marco Rubio to refuse to take NRA money in the future. Rubio would not refuse.

Litman said on CBSN that this issue is "too important not to speak up on this. There's a lot of way to do something on gun violence ... this is our way in."

Litman is the former email marketing director for Hillary Clinton's campaign. She says that since Run for Something launched on Inauguration Day 2017, 16,000 milliennials have signed up to run for office. In 2017, Run for Something endorsed 72 candidates in 14 states -- and 35 won.

"These people are fired up," Litman said. "They're sticking with it – they're changing their lives in order to change their communities because they care about solving problems. They are pissed off at the status quo, and they are not settling – they are so inspiring and they give me a lot of hope for the future."