A new poll has U.S. Sen. John Cornyn up by 17 points on challenger Rick Noriega.

The Rasmussen Reports survey has the incumbent Republican at 52 percent and the Democratic challenger at 35 percent.

The takeaway for Cornyn: It's the first public poll that gives him a reelect number above 50 percent.

And the takeaway for Noriega: He's never run statewide but has 35 percent of Texas with him, while Cornyn, who's run statewide several times (Texas Supreme Court, attorney general, Senate) is hovering around 50 percent.

The same pollster had the two four points apart a month ago. Neither has done any advertising or generated much in the way of headlines, so it's hard to say what moved the needle.

In their write-up, the Rasmussen folks say Cornyn is viewed unfavorably by 31 percent of Texans; Noriega by 39 percent. Cornyn is viewed positively by 56 percent; Noriega by 43 percent. The pollster says voters don't have firm opinions about either candidate.

What do they think about other incumbents? According to Rasmussen, Gov. Rick Perry is viewed favorably by 34 percent and unfavorably by 27 percent; President George W. Bush favorably by 40 percent and unfavorably by 40 percent.

The company surveyed 500 votes by phone on June 2. The margin of error is +/- 4 percent.