The death penalty is like gun rights in Texas politics: Candidates don’t dare get in the way of either. But Republican Greg Abbott, the favorite to succeed Gov. Rick Perry, must soon make a decision as attorney general that could disrupt the nation’s busiest death chamber. It’s an election-year dilemma for Abbott. But in Texas, it’s one that Democratic rival Wendy Davis can’t easily exploit, illustrating the difficulty of navigating the issue in such a pro-death penalty state. Abbott must soon decide whether to stick with his earlier opinions that Texas must disclose the source of the execution drugs it...