Kennedy, Roberts and Scalia are arguably the three most prominent members of the Supreme Court. Chief Justice Roberts and Kennedy often find themselves as the swing votes in cases divided along ideological lines. For example, Roberts sided with the liberal justices to uphold the Affordable Care Act in 2012, while Kennedy has been the deciding vote on recent gay rights cases, including the most recent one that legalized same-sex marriage. Scalia is the most vocal member of the court’s conservative wing — known for his biting and colorful dissenting opinions.
It appears their high-profile deciding votes on same-sex marriage and the Affordable Care Act have endeared Kennedy and Roberts to Democrats and turned Republicans off to them, even though all were appointed by a Republican president and typically vote more with the court’s conservative wing than its liberal wing.