In the statement released by his office, Tim Johnson thanked the people of South Dakota for their support.
"This has been an unexpected journey and there is a long road in front of me. I am determined and focused on my recovery, and I look forward to returning to the Senate on behalf of South Dakota," he said.
“This has been an unexpected journey, and there is a long road in front of me.”Sen. Tim Johnson
Photos of Johnson are posted on his Senate Web site. He's seated in a wheelchair with his right arm propped up by a pillow while reading a newspaper. He looks thinner.
Johnson is undergoing physical, occupational and speech rehabilitation. Doctors say he's making significant progress, with the focus on balance training and speaking faster.
Johnson's illness and ensuing absence from the Senate have highlighted his party's tenuous one-seat advantage in the chamber. He has been recovering at a private rehabilitation facility since leaving George Washington University Hospital last month.
Johnson's office has said his recovery is expected to take several months, though he has been doing some work from his bed.
Johnson is up for re-election in 2008 and could face a tough race if he runs again in Republican-leaning South Dakota.
(The Associated Press contributed to this report)