WASHINGTON — When George W. Bush first ran for president, he liked to say he had inherited half of his father’s friends and all of his enemies. For Jeb Bush, now preparing his own bid for the White House, that may ring familiar.

His brother’s enemies have made themselves known in recent weeks as Jeb Bush has struggled to formulate his own take on the decisions made during the last Bush presidency. But perhaps just as important for the presumed candidate has been the challenge in winning over his brother’s friends.

While George W. Bush himself and many in his circle, especially those closest to the family, are enthusiastic about the prospect of a third Bush presidency, many of the Republican foot soldiers who worked for the former president in his campaigns and his administration have not rushed to back his brother’s emerging operation.

A sampling conducted largely by email of about 120 people who worked for George W. Bush — from cabinet secretaries to foreign policy advisers to advance aides — found about 25 who said they were supporting his younger brother. Fifty others said they were neutral or supporting another candidate, while the rest did not respond, apparently passing up a chance to declare allegiance to the next Bush candidacy.