WASHINGTON, March 24 - Gov. Jeb Bush's last-minute intervention in the case of Terri Schiavo, even after the president had ended his own effort to keep her alive, may have so far failed in a legal sense, but it has cemented the religious and social conservative credentials of a man whose political pedigree is huge and whose political future remains a subject of intense speculation. On one level, the Florida governor's emergence as the most prominent politician still fighting, despite a string of court and legislative defeats, to have a feeding tube reinserted in Ms. Schiavo was very much in...