(CBSNEWS) — Chief Justice John Roberts initially sided with the Supreme Court’s four conservative justices to strike down the heart of President Obama’s health care reform law, the Affordable Care Act, but later changed his position and formed an alliance with liberals to uphold the bulk of the law, according to two sources with specific knowledge of the deliberations.

Roberts then withstood a month-long, desperate campaign to bring him back to his original position, the sources said. Ironically, Justice Anthony Kennedy – believed by many conservatives to be the justice most likely to defect and vote for the law – led the effort to try to bring Roberts back to the fold.

“He was relentless,” one source said of Kennedy’s efforts. “He was very engaged in this.”

But this time, Roberts held firm. And so the conservatives handed him their own message which, as one justice put it, essentially translated into, “You’re on your own.”

  • Text smaller
  • Text bigger
Note: Read our discussion guidelines before commenting.