Edward Kennedy

Doctors have diagnosed Sen. Edward Kennedy with a malignant brain tumor, after he suffered a seizure on Saturday.

President Bush was said to be "deeply saddened" by the news, per The Page.

"Laura and I are concerned to learn of our friend Senator Kennedy's diagnosis. Ted Kennedy is a man of tremendous courage, remarkable strength, and powerful spirit. Our thoughts are with Senator Kennedy and his family during this difficult period. We join our fellow Americans in praying for his full recovery."

John McCain released this statement: "We hope and pray his doctors will be able to effectively treat his condition and that he will experience a full recovery. I have described Ted Kennedy as the last lion in the Senate, and I have held that view because he remains the single most effective member of the Senate.”

Kennedy's endorsement of Barack Obama was followed by an aggressive schedule of campaigning for the candidate, including this appearance in East Los Angeles on Feb. 1.

But his campaign for the presidency in 1980, where he nearly toppled incumbent Jimmy Carter, is still a fabled moment in recent political history, topped by his speech at the Democratic National Convention that year.

Here's a clip of that campaign, from a documentary called "The Made-for-TV Presidency."