But several donors who have had private conversations with Paul about his foreign policy said those talks have not assuaged their concerns. And unlike his father, whose intensely supportive base was fairly contained, they worry that Paul’s smoother approach could make him a contender. “Can he win Iowa, yes. Can he win New Hampshire, yes. Can he win the nomination, maybe — and that’s scary,” says one former Mitt Romney bundler at the conference who did not want to be named.

On the margins of the conference, where attendees heard from four potential 2016 candidates who advocated for a strong American foreign policy and support for Israel, five donors huddled with a reporter pledged to reach into their deep pockets to ensure Paul doesn’t win the GOP nomination.

“The best thing that could happen is Ted Cruz and Rand Paul run and steal each other’s support,” says one of the donors, “but if not, we’ll be ready to take Paul down.”…

“Paul hasn’t — and probably will never — win the trust of the pro-Israel community,” says Noah Pollak, executive director of the conservative Emergency Committee for Israel, which ran ads against the elder Paul. “But his foreign policy problems run far deeper. His mustering of fake outrage over issues like Tomahawk-missile cuts and the persecution of Middle East Christians are a shiny-object strategy intended to contradict the correct impression that, at his core, he is more or less an isolationist.”