A poll released Tuesday by Quinnipiac University has Senator Ted Cruz leading his Democratic challenger, Beto O'Rourke by 9 percent. The difference in this poll and others released by Quinnipiac in the past on this race is who was surveyed.

In the poll released Tuesday, Quinnipiac surveyed "likely" voters instead of "registered" voters. Cruz leads O'Rourke among likely voters 54 to 45 percent. In Quinnipiac's poll in August of registered voters, Cruz lead by 6 percent.

According to the poll, voters approve of the job Cruz is doing 53-44 percent and Cruz has a 52 percent favorability rating. O'Rourke had a split 43-43 favorability rating in this poll.

The poll was released days before Friday's scheduled debate in Dallas between the two candidates. On Saturday, Senator Ted Cruz will host a rally in Lubbock.