Kirk is playing with fire. Taking on Phil Gramm will only solidify the conservative base for Cornyn.
I tend to agree. I have actually been impressed with the civil manner in which Kirk has been running his campaign. I think it served him well, attracting some Pubbies and indies. Now he's apparently getting irked at Gramm's comments and Cornyn's ads. If Kirk is perceived as mudslinging and turning this into a partisan battle, I think that plays to Cornyn's advantage given TX's demographics.
Then again, it's pretty easy for me to "talk" way out here in VA. :-)