As he weighs whether to jump into the 2012 Republican presidential race, Texas Gov. Rick Perry has been dialing GOP establishment bigwigs across the country. In phone calls that sometimes stretch more than a half hour, Perry asks the same questions: Is the door open for a new candidate? And how wide is it open? Perry is finding that a vast reservoir of the Republican Party establishment — broadly defined to include elected officials, donors, strategists and activists whose support fuels presidential campaigns — is so far untapped, according to interviews conducted Monday and Tuesday with 19 major donors, strategists...