I can’t claim ownership of this theory, which comes from a very shrewd Texas Democrat, but it sounds plausible to me.
The reason had nothing to do with Bill White not revealing his taxes. It had nothing to do with Perry being afraid to debate White. Perry was never afraid of debating Bill White.
He was afraid of Kathie Glass.
Glass is the Libertarian nominee for governor. The only person who came close to imperiling Perry’s reelection campaign was another Libertarian, Debra Medina. In the second debate before the Republican primary, she assailed him on his home-turf issues, immigration, border security, taxes, eminent domain. She is the only opponent who has ever been able to get to Perry’s right. After that debate, Medina soared in the polls. I wrote at the time that Perry was in real danger, that if Medina could get $5 million or so, she could win the nomination. But Medina’s appearance on the Glen Beck radio program proved to be her undoing when she wouldn’t take a position on whether the US government was behind the 9/11 attacks on the World Trade Center.
Like Medina, Glass would have attacked Perry from the right. Perry can handle opponents in the center (Hutchison) or on the left (Sanchez, Bell, White). What he can’t handle is someone who attacks him from the right, on issues that are near and dear to the right, like eminent domain and border security. Glass is no Debra Medina, but she still would have made Perry very uncomfortable.