Feinstein, who at 89 is the oldest member of Congress, has been recovering from shingles at her home in San Francisco. During that period she has missed roughly 90 votes, including a number in the critical Senate Judiciary Committee.
In a statement released Wednesday, Feinstein, who was using a wheelchair as she returned to the Capitol, said she is "prepared to resume my duties in the Senate," but with a "lighter schedule" as she continues her recovery.
"Even though I've made significant progress and was able to return to Washington, I'm still experiencing some side effects from the shingles virus," she said. "My doctors have advised me to work a lighter schedule as I return to the Senate. I'm hopeful those issues will subside as I continue to recover."
Feinstein's office said her lingering side effects include vision and balance impairments and that would also at times need to use a wheelchair to travel around the Capitol.
Such was the case on Wednesday afternoon when she made her first appearance back on Capitol Hill for an afternoon vote.
"Much better," she told an ABC News reporter who asked how she was doing.
Democratic Senate Majority Leader Chuck Schumer assisted Feinstein onto the Senate floor to vote.
Earlier in the morning, Schumer had welcomed Feinstein back during his morning remarks.
"On a happy note, I join my fellow senators in welcoming back our dear friend and esteemed colleague, Dianne Feinstein. It's so good to see her back here in the Senate, ready to get back to work," Schumer said. "I've been in touch with Sen. Feinstein over the past few weeks, and I can report she's exactly where she wants to be: ready to do the things she loves most, serving the people of California."
"So, Sen. Feinstein, we are so happy to see you," he added. "Welcome back!"
Among the most prominent Democrats who had called for Feinstein to resign is Bay Area Congressman Ro Khanna.
In a statement on Wednesday, he said: "I am very glad that Sen. Feinstein is feeling better and hopeful that she will be able to fulfill her duties upon her return. The people of California deserve strong representation and a Senator who can vote to advance President Biden's judicial nominees and protect Americans' fundamental rights. The three-month absence hurt our agenda, and time will tell on the future."
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