AUSTIN, Texas -- - It's a twist in Texas' top race - Cruz vs. O'Rourke. 

In a new poll, Democratic US Senate Candidate Beto O'Rourke is leading Republican incumbent Ted Cruz for the first time. But it comes one day after another poll found Cruz up by nine. So, why such a big difference?  The simple answer: poll results aren't an exact measurement of the voting population. 

For the average voter, it's hard to make sense of who's actually ahead.

"You may want to do what a lot of professionals do and that's average them all," said polling expert Sherri Greenberg.  

Greenberg, with the LBJ School of Public Affairs at UT Austin, has been studying the polls and says Cruz has the advantage simply because there are more registered Republicans in Texas. She further said that no matter the poll, O'Rourke will have to woo some Republicans in order to win in November. 

"On the O'Rourke side, he may be in a situation where he needs to bring over maybe female Republican voters, or more Republican voters, or independents or bring new voters to the polls," Greenberg said. 

And those voters do exist. Jennifer Harris is a registered Republican, and always has been.  She says she's voting for O'Rourke over Cruz in November. 

"I think the fact that he's willing to listen and wants to appeal to and hear from all people, whether they're Republicans or Democrats or independents, I think that's vitally important," said Harris.  

Harris' vote is an important one for O'Rourke, who's banking on bringing more like her his way in order to pull off a huge upset on Election Day.

At the end of the day, experts say these polls only carry so much weight. As we approach Election Day, it's important that voters are researching these candidates on their own, and making the best decision for themselves, regardless of poll results.