(huffpost)Hillary Clinton has summoned top donors and backers to attend her New York speech tomorrow night in an unusual move that is being widely interpreted to mean she plans to soon suspend her campaign and endorse Barack Obama - not tomorrow night but within a day or two. Obama and Clinton spoke Sunday night and agreed that their staffs should begin negotiations over post-primary activities, according to reliable sources. In addition to seeking Obama's help in raising money to pay off some million-plus in debts, Clinton is known to want Obama to assist black officials who endorsed her and who are now taking constituent heat, including, in some cases, primary challenges from pro-Obama politicians. "This has never happened before," one donor said, referring to the personalized request by email to attend the event in New York Tuesday night. Obama is expected to claim enough delegates to put him over the top that night at a separate event in St. Paul.