CHARLOTTE, N.C. -- The rematch of a close 2016 North Carolina congressional primary may hinge as much on which Republican candidate more vigorously supports President Donald Trump as who more successfully mobilizes Christian conservatives.

• Three Republican candidates are trying to appeal to Christian voters who support President Trump
• Candidates in the race: U.S. Rep. Robert Pittenger, Mark Harris and Clarence Goins
• FULL COVERAGE: Decision 2018

Only 134 votes separated U.S. Rep. Robert Pittenger and the Rev. Mark Harris for the Republican nomination in the south-central 9th District. It includes parts of Charlotte and its suburbs, along with poor counties and areas close to Fort Bragg.

MORE: What District 9 voters should know before heading to the polls

Harris and Pittenger are again the top candidates in Tuesday's primary. They are again touting their evangelical credentials. With Trump now in office, each has accused the other of failing to support fully the president or his agenda.

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The winner of the three-candidate race is likely to face a well-funded Democratic nominee in the fall.