ABC News’ Jonathan Karl reports: The lion of the Senate is back. After spending almost all of the winter in Florida, Senator Ted Kennedy, D-Mass., has returned to Washington, where he intends to remain for the foreseeable future. A source in Kennedy’s office says the senator gave approximately 100 of his Senate staff members a pep talk Tuesday morning, making it clear that even with his illness, he is determined to play a key role in getting health care reform passed this year. The talk lifted spirits of Kennedy staffers who have seen very little of Kennedy since he was diagnosed with brain cancer last May, but they know he is suffering from a serious illness that will limit the amount of work he is able to do. "You should expect to see him more," said one Kennedy aide, "but he is still balancing his work with his treatment plan." Kennedy got back to work Monday night, casting a key procedural vote in favor of bill he co-sponsored with Sen. Orrin Hatch, R-Utah, to expand the national service corps. On Tuesday, in addition to meeting with his staff, Kennedy met with Gov. Kathleen Sebelius, D-Kan., President Obama’s nominee to be Secretary of Health and Human Services.