Stanley Kurtz observes that "It’s been noted how little difference a raft of high profile endorsements by the Kennedy clan and other heavy hitters in Massachusetts made to the outcome there." I have heard that from a lot of people. I think those people may have unrealistic expectations. Look at this chart from Pollster.com which fairly accurately forecast the Bay State as a solid Clinton win. That's still a state in which Obama achieved a massive late-stage surge, helped along by high-profile endorsements. If he'd had another two weeks to campaign, maybe he would have closed the gap. Or maybe not. Certainly if he'd had more time to build on the endorsements in order to construct an actual Massachusetts ground game that would have helped. But the idea that Ted Kennedy just bounced off the electorate isn't well supported by the evidence.
Matthew Yglesias is a former writer and editor at The Atlantic.