This is an interesting read by someone who appears to be a SBS supporter, however one feels about the ultimate conclusion.
http://www.newyorker.com/news/john-cassidy/why-is-president-obama-embracing-hillary-clinton
A couple of weeks ago, on NBC’s “Meet the Press,” Denis McDonough, the White House chief of staff, appeared to indicate that President Obama wouldn’t be backing anyone in the Democratic primary. The President would vote in the Illinois primary, on March 15th, and campaign for whichever candidate emerged from the process, McDonough said. Now, though, Obama has come very close to issuing a public endorsement of Hillary Clinton.
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Was Obama just shooting the breeze with a guest in the Oval Office who happened to be carrying a tape recorder? Hardly. It is much more plausible that the President was sending a supportive message to an embattled candidate whom he sees as the best option to replace him, in order to safeguard the electoral position of the Democratic Party and preserve his legacy as a center-left reformer.
For all the differences they had in 2008, some of which lingered, Obama and Clinton both represent the centrist, pragmatic approach to politics that has dominated the Democratic Party since the nineteen-eighties. A victory for Sanders and his insurgent left-wing populism would represent a sharp break with the moderate tradition. In the opinion of many Democrats in the White House and on Capitol Hill, it would also set up the Party for defeat come November, not just in the Presidential race but in congressional elections. And, from Obama’s perspective, it would place a shadow over his biggest achievements, particularly the Affordable Care Act, which Sanders has described as merely a first step in transforming the health-care system.
If the Republicans win the Presidential election and strengthen their grip on Congress, they are likely to repeal large parts of the Affordable Care Act and roll back many of President Obama’s executive orders in other areas, such as environmental regulation. If Sanders were to become President, he would presumably seek to build on Obama’s policies, but there would still be a significant change in approach. In part to try to prevent either of these things from happening, a number of former Obama Administration officials are working for the Clinton campaign. John Podesta, Clinton’s campaign chairman, worked at the White House under Obama. So did Jennifer Palmieri, the Clinton campaign’s director of communications. Joel Benenson, a senior strategist and pollster for the Clinton campaign, carried out a similar role in Obama’s 2008 and 2012 campaigns. The Sanders campaign doesn’t have these sorts of personal ties to the White House.