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Several explanations have been offered for Yale’s representation in national elections since the end of the Vietnam War. Various sources note the spirit of campus activism that has existed at Yale since the 1960s, and the intellectual influence of Reverend William Sloane Coffin on many of the future candidates. Yale President Richard Levin attributes the run to Yale’s focus on creating "a laboratory for future leaders," an institutional priority that began during the tenure of Yale Presidents Alfred Whitney Griswold and Kingman Brewster. Richard H. Brodhead, former dean of Yale College and now president of Duke University, stated: "We do give very significant attention to orientation to the community in our admissions, and there is a very strong tradition of volunteerism at Yale." Yale historian Gaddis Smith notes "an ethos of organized activity" at Yale during the 20th century that led John Kerry to lead the Yale Political Union's Liberal Party, George Pataki the Conservative Party, and Joseph Lieberman to manage the Yale Daily News. Camille Paglia points to a history of networking and elitism: "It has to do with a web of friendships and affiliations built up in school." CNN suggests that George W. Bush benefited from preferential admissions policies for the "son and grandson of alumni", and for a "member of a politically influential family." New York Times correspondent Elisabeth Bumiller and The Atlantic Monthly correspondent James Fallows credit the culture of community and cooperation that exists between students, faculty, and administration, which downplays self-interest and reinforces commitment to others.

What does Elisabeth Bumiller believe the reasoning behind the amount of political Yale alumni is?
the culture of community and cooperation