Trump led the primary polls from the beginning and never lost his lead.

For a time in July, after her strong first debate performance, she rose towards the top of some primary polls.

The biggest advantage of state-based primary polls compared to national primary polls is they reference actual elections, since there is no national primary.

Carson, a favorite of conservative activists, is neck-and-neck with Trump at the top of Republican primary polls a year before the November 2016 presidential election.

Carson, a favorite of conservative activists, is tied with Trump at the top of Republican primary polls a year before the November 2016 presidential election.

Primary polls are considerably less predictive than general election polls pitting two nominees against each other.