INDIANAPOLIS, Indiana – Sen. Joe Donnelly (D-IN) clapped along at a March for Our Lives gun-control event in Indianapolis on Saturday, an unusual move for a vulnerable red-state senator, one that his 2018 Republican opponents were quick to criticize as indicating Donnelly’s lack of support for Second Amendment rights.

Gun control continues to dominate the airwaves this week. Saturday’s protests in Washington, DC, were duplicated in statehouses nationwide, including Indiana’s. Retired Supreme Court Justice John Paul Stevens’s op-ed this week calling for the outright repeal of the Second Amendment right to keep and bear arms has highlighted what the National Rifle Association (NRA) and other gun-rights leaders have been saying throughout these protests: this is an effort to deprive ordinary Americans of the basic means to keep their families safe, rather than target a small class of firearm features.

Many red-state senators up for reelection in 2018 have avoided being associated with March for Our Lives, worried that the far left’s zeal for taking away gun rights altogether would eventually become clear and that a backlash from moderate gun owners could cost those Democrats dearly in November.

Donnelly appears not to have gotten that political memo, deciding to participate in Saturday’s anti-gun protest in the nation’s capital, joined by far left Rep. Andre Carson (D-IN) – rated “D” by the NRA for his opposition to the Second Amendment to the Constitution – and others who are calling for banning guns.

Two Republican congressmen in Indiana who are vying for the opportunity to oust Donnelly from the Senate spoke out in response to the anti-gun protests.

Rep. Todd Rokita spoke broadly, criticizing the establishment media for their coverage of the anti-gun crusade.

“Typical of the media elite to not give the same level of attention to the annual March for Life in D.C. and across Indiana, which draws hundreds of thousands of people every year,” Rokita told Breitbart News in an exclusive, referring to the annual pro-life event that advocates for the Supreme Court to overrule Roe v. Wade.

“Americans have always had guns,” Rokita continued. “We have a cultural problem, and violence is a manifestation of a problem in our culture. That is what needs to be addressed.”

Rokita’s leading rival for the nomination took a different tack, taking on his possible general election opponent by name.

“Typical Sen. Donnelly … tries to have it both ways on almost every issue,” said Rep. Luke Messer in a separate exclusive statement to Breitbart News, directing his criticism directly against his state’s Democrat senator. “Sen. Donnelly takes money from the NRA when it’s politically convenient but touts gun control and shows his true colors when liberal pressure builds.”

“Gun bans are not the answer,” Messer continued. “I support the Second Amendment. I’ve repeatedly voted to protect the Second Amendment, and I will always shoot straight with Hoosiers about my support for gun rights.”

Republicans see the Indiana Senate seat held by Donnelly as a promising opportunity to build on their numbers in that chamber, possibly helping Republicans actually attain a working majority in the narrowly divided Senate, one where Democrats are repeatedly blocking President Donald Trump and a conservative agenda.

The Republican primary for U.S. Senate will be held on May 8.

Ken Klukowski is senior legal editor for Breitbart News. Follow him on Twitter @kenklukowski.