Many political analysts say there's not a lot of daylight between Ted Cruz and David Dewhurst on major issues like healthcare, social security, and the economy.
Brandon Rottinghaus is an Associate Professor of Political Science at the University of Houston. He says Cruz was able to get the backing of so many Tea Party activists because he made a special effort to speak their language.
"Reverence of the constitution, very conservative ideology, picking out policy positions laid out by the higher-ups of the Tea Party. Ted Cruz, I think, naturally courted that vote."
Rottinghaus says another factor working in Cruz's favor is that Tea Party supporters generally favor candidates who've never held office. Several polls put Cruz and Dewhurst in a statistical tie. But Rottinghaus says if you drill down to the responses from those who identify as either "very conservative", or members of the Tea Party, they favor Cruz by a 60 to 70 percent margin.
"You're talking about the most dedicated Republican party primary voters around. And if those individuals come into the polls in the way they often do, I think you're going to have a slight edge for Ted Cruz."
As for Dewhurst, Rottinghaus says the Lieutenant Governor will rely more on campaign ads, along with smaller, more focused campaign events, and the endorsements from establishment Republicans to help him clinch the GOP senate nomination on Tuesday.