Washington (CNN) One US president spoke with Sen. Susan Collins several times ahead of her announcement Friday that she would support Brett Kavanaugh's nomination to the Supreme Court -- and he's been out of office for nearly a decade.

Former President George W. Bush called a number of senators in recent weeks, and had several conversations with Collins to reassure the key Republican vote about Kavanaugh's character and temperament, a person familiar with the matter tells CNN.

Kavanaugh's confirmation was thrown into doubt after a tense Senate Judiciary Committee hearing in which Christine Blasey Ford alleged the Supreme Court nominee had sexually assaulted her when they were in high school in the 1980s. Kavanaugh has denied all the allegations against him.

Collins supported an additional FBI background check into the accusations, which stoked speculation that she might then break with Republicans and vote against Kavanaugh's nomination, but the results of that investigation -- along with Bush's calls -- paved the way for her support Friday.

"I do not believe that these charges can fairly prevent Judge Kavanaugh from serving on the court," the senator said on the Senate floor.

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