"His approach to endorsements is to wait until the grassroots unite behind a solid conservative candidate," Hoskins said. "This has happened in several Senate races, but it hasn't happened in the presidential race." Earlier this month, Cruz got a boost from the Club for Growth, another group that has endorsed his underdog candidacy. The Club launched two TV ads that hit Dewhurst. For Cruz to have have success chasing down the frontrunning Dewhurst, he'll need major help from his national allies, as the lieutenant governor will have a financial and name ID advantage.