An aging Senate contends with time and illness

76-year-old Kennedy's malignant brain tumor Tuesday was a heartbreaker even for this wizened group, which has seen spouses and friends fall before them.

Byrd, 90, wept as he prayed for "my dear, dear, dear friend, Ted Kennedy."

Specter, 78, is balding from treatments for his second bout with cancer. Specter himself once received a diagnosis of brain cancer — and a grim prediction of six weeks to live. Despite his experience with the deadly disease, he told reporters that hearing the news about Kennedy was "just overwhelming."

The fifth-term Pennsylvania Republican has said many times that staying on the job through treatment has been key to his survival.

Age is just a number