Despite the tremendous importance of politics in Supreme Court nominations, the single most important determinant of a successful confirmation is the qualifications of the nominee. We have measured the qualifications of all nominees since Hugo Black (1937) by content analyzing newspaper editorials from leading newspapers at the time of their nominations [see table below]. By this standard, Miers falls near the bottom of the stack. Thus, her withdrawal is not surprising.
What is unusual about her nomination is the degree to which it stirred opposition from the President’s co-partisans. While Abe Fortas’s 1968 defeat for the Chief Justice position came in substantial part at the hands of Democrats, those were Southern Democrats who could hardly be said to be of the same party as the national Democrats that Lyndon Johnson and Abe Fortas represented.
– Jeffrey Segal and Lee Epstein, authors of Advice and Consent: The Politics of Judicial Appointments