The North Carolina Senate race could end up making or breaking a potential Democratic majority this fall. Sen. Thom Tillis remains one of the Republicans' most endangered incumbents and the Mar. 3 primary should bring some clarity of who he'll face in November and give hints to how much more competitive the race could become.

Former state Sen. Cal Cunningham, 46, has been endorsed by the Democratic Senatorial Campaign Committee and is still the favorite to win the nomination over his next closest competitor, state Sen. Erica Smith. Public polling this week shows Cunningham is on track to win the nomination outright, clearing the 30% threshold and avoiding a May 12 runoff.

A WRAL/SurveyUSA poll gave Cunnigham a 42%-17% lead over Smith, which Democrats say tracks with Cunningham's internal polling. Thirty-four percent of voters are still undecided, and there are three other candidates also on the ballot.

But heavy outside ad spending in the final weeks of the race has given this race some late drama and added uncertainty. Starting Feb. 4, the mysterious Faith and Power

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