A Wisconsin county sheriff whose outspoken pro-Second Amendment views turned his re-election campaign into a battle between gun control groups and the National Rifle Association was leading early Wednesday in a close fight against his Democratic primary challenger. 

With 100 percent of precincts reporting, Milwaukee County Sheriff David Clarke Jr. had garnered 52 percent of the vote to 48 percent for Chris Moews, a Milwaukee police lieutenant. Clarke's margin was over 4,600 votes out of nearly 109,000 cast. However, Moews refused to concede, saying that there were over 6,000 absentee votes that had yet to be counted. 

"We're not ready to call it a night," Moews told his boisterous supporters early Wednesday. 

Clarke did not directly address the returns when he spoke to his supporters, but said only "We're happy with where we are," and later added "When the final results are in, I believe we're going to have another four years."

Clarke made headlines last year after he spent money on a radio ad that urged citizens to enroll in firearms classes following budget cuts. He told residents in the 30-second commercial to “point that barrel center mass and pull the trigger” because “911 is not our best option.”

He also said that personal safety is no longer a spectator sport and told citizens, "I need you in the game."

The primary race was a rematch of the one four years ago in which Clarke beat Moews by six percentage points. Since no Republicans are in the race, the winner of the Democratic primary will most likely become the next county sheriff.

Unlike in 2010, Moews was armed with money aimed at taking down Clarke.

Former New York City Mayor Michael Bloomberg - who through his political group has publicly committed to spending $50 million on gun-control politics in 2014 – paid $150,000 to air a series of television ads targeting Clarke’s conservative pro-gun policies.

The money from Bloomberg’s Independence USA super PAC was more than what Clarke and Moews spent on their entire campaigns combined.

Bloomberg spokesman Howard Wolfson told the Wall Street Journal on Monday that he decided to get involved in the sheriff’s race because it allowed him to shape policy on a local level.

“The issue of guns is one that (Bloomberg) cares an awful lot about and there’s a very clear contrast on that issue in this race,” Wolfson told the newspaper.

But Bloomberg wasn’t the only person pumping cash into the primary.

The Greater Wisconsin Committee spent $400,000 on its own anti-Clarke ads.

For his part, Clarke spoke at the National Rifle Association’s annual meeting in April. The NRA, who calls Clarke a “rising national star,” has come to Clarke’s defense, soliciting donations from its members on his behalf and buying online ads for his re-election bid.

“Make no mistake: Sheriff Clarke is fighting the reelection battle of his life right now because he dared to stand on principle by standing up for you, me and the NRA,” Chris Cox, executive director of the NRA’s Institute for Legislative Action, said.

"Am I big on a person's right to be able to defend themselves? Yes. You know why? Because it's a natural right,” Clarke recently told Wisconsin News Radio 620 WTMJ.

Moews had a different take.

"If I have the opportunity to defend myself and my family I will do so to the best of my abilities but I’m certainly also going to call 911 if I have the ability because I need the cavalry to come and help me," Moews told WTMJ at the same political event.

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