Sestak, a retired Navy admiral and 2-term Democratic Pennsylvania congressman, criticized Israel’s blockade of Gaza. He then ran in a Senatorial primary bid against Arlen Specter, the Israel partisan who had just switched from Republican to Democrat. The Dem establishment, including Obama, backed Specter, but Sestak won the primary. Conservative pro-Israel groups spent millions targeting Sestak, who then narrowly lost the general election to Republican Pat Toomey…