WASHINGTON â President Barack Obama will nominate Solicitor General Elena Kagan to the Supreme Court, a person familiar with the president's thinking said Sunday night. The move positions the court to have three female justices for the first time in history. The source spoke on condition of anonymity because the decision had not been made public. Obama will announce his choice at 10 a.m. Monday in the East Room of the White House. Known as sharp and politically savvy, Kagan has led a blazing legal career: first female dean of Harvard Law School, first woman to serve as the top Supreme Court lawyer for any administration, and now first in Obama's mind to succeed legendary Justice John Paul Stevens. At 50 years old, Kagan would be the youngest justice on the court, one of many factors working in her favor. She has the chance to extend Obama's legacy for a generation. Kagan has clerked for Thurgood Marshall, worked for Bill Clinton and earned a stellar reputation as a student, teacher and manager of the elite academic world. Her standing has risen in Obama's eyes as his government's lawyer before the high court over the last year. Yet Kagan would be the first justice without judicial experience in almost 40 years. All of the three other finalists she beat out for the job are federal appeals court judges, and all nine of the current justices served on the federal bench before being elevated. Kagan's fate will be up to a Senate dominated by Democrats, who with 59 votes have more than enough to confirm her, even though they are one shy of being to halt any Republican stalling effort. For the second straight summer, the nation can expected an intense Supreme Court confirmation debate even though, barring a surprise, Kagan is likely to emerge as a justice.