WASHINGTON (AP) _ Political leaders of both parties suddenly riveted their attention on a stricken Democratic senator from South Dakota. The incoming Senate majority leader rushed to his bedside. A media throng assembled outside George Washington University Hospital.
It might seem like an inordinate fuss for a two-term senator not well known outside his home state or the corridors of Capitol Hill.
But as Sen. Tim Johnson, 59, remained in critical condition Thursday recovering from emergency brain surgery, Democratic control of the new Senate hung in jeopardy.
Johnson underwent overnight surgery to repair bleeding inside his brain.
He took ill just three weeks before Democrats are set to take fragile 51-49 rule over the new Senate. Democrats seized majority control of both chambers of Congress from Republicans in November midterm elections.
If Johnson were to leave office, a replacement would be named by South Dakota's Republican governor, Mike Rounds. A Republican appointee would create a 50-50 tie and effectively allow the GOP to retain Senate control because of Vice President Dick Cheney's tie-breaking vote.
Johnson was described as recovering and holding his wife's hand. He was on "an uncomplicated postoperative course," the U.S. Capitol physician said after visiting him Thursday afternoon. Johnson suffered a hemorrhage in his brain caused by a rare and sometimes fatal condition.
"He has been appropriately responsive to both word and touch. No further surgical intervention has been required," said the physician, Adm. John Eisold. He had said earlier, "The senator is recovering without complication."
Johnson was responding to the voice of his wife, Barbara, and following directions after the surgery, the senator's office said in a statement. "He was reaching for and holding her hand."
Johnson was rushed to the George Washington University Hospital at midday Wednesday after becoming disoriented and stammering during a conference call with reporters.
Eisold, the Capitol physician, said doctors stopped bleeding in Johnson's brain and drained the blood that had accumulated there. "It is premature to determine whether further surgery will be required or to assess any long-term prognosis," Eisold said.
On Thursday afternoon, Johnson underwent an additional procedure to prevent blood clots. The procedure is standard after surgery, said Julianne Fisher, Johnson's spokeswoman. Otherwise, she said, there were no new developments. "No news is good news," she said.
Johnson's condition, known as AVM, or arteriovenous malformation, causes arteries and veins to grow abnormally large, become tangled and sometimes burst. The condition is often present from birth.
Johnson spokesman Noah Pinegar said the senator's diagnosis was a surprise. "No one was aware of it, including Tim," he said.
Sen. Harry Reid, D-Nev., who is to become majority leader when the new Senate convenes on Jan. 4, said, "We're all praying for a full recovery. We're confident that will be the case."
Reid, who visited Johnson at the hospital Wednesday night and Thursday, told reporters the senator "really looks good." However, Reid declined to provide any details of Johnson's medical condition.
Politically, "there isn't a thing that's changed," he said, adding that he was keeping incoming Senate Republican leader Mitch McConnell of Kentucky "totally advised" of developments.
Outgoing Senate Majority Leader Bill Frist, R-Tenn., visited the hospital Thursday afternoon.
Senate historian Donald Ritchie said senators serve out their terms unless they resign or die. He said there was precedent for senators remaining in the Senate even though illness kept them away from the chamber for long periods.
Just this year, Sen. Jay Rockefeller, a West Virginia Democrat, missed three months of votes because of back surgery. Sen. Joseph R. Biden Jr., D-Del., was away for seven months in 1988 after undergoing surgery for brain aneurysms.
In 1969, another South Dakota senator, Karl Mundt, a Republican, suffered a stroke while in office. Mundt continued to serve until the end of his term in January 1973, although he was unable to attend Senate sessions and was stripped of his committee assignments by fellow Republicans in 1972.
The White House offered best wishes.
"Our prayers are with Senator Johnson," said White House Press Secretary Tony Snow. "Look, he's a great guy, and it's one of these things where everybody's concerned and our thoughts and prayers are with him, his family, his staff, his colleagues."
Johnson, who turns 60 in two weeks, was taken to the hospital by ambulance after experiencing what his office initially said was a possible stroke.
In a conference call with reporters, Johnson at first had answered questions normally but then had begun to stutter. He paused, then continued stammering before appearing to recover and ending the call.
Johnson spokeswoman Fisher said that after making the call from the recording studio in the basement of the Capitol, the senator walked back to his office but appeared to not be feeling well.
The Capitol physician came to his office and examined him, and it was decided he should go to the hospital.
Arteriovenous malformation is believed to affect about 300,000 Americans, according to the National Institute of Neurological Disorders and Stroke. The institute's Web site said only about 12 percent of those have any symptoms. The symptoms, which range in severity, can include severe headaches, memory loss and dizziness.
It's common to take several days for someone to wake up after AVM surgery, said Dr. Sean Grady, neurosurgery chairman at the Hospital of the University of Pennsylvania. Someone who is awake and alert and talking in the first day or two typically has a shorter recovery _ in the range of four to eight weeks, he said. If it takes longer to wake up, it in turn takes more months to recover.
"We wouldn't make any immediate long-term prognoses for at least one to two days," he cautioned. "There can be a period of time where the brain is still swollen and the patient may have trouble responding."
Barbara Johnson, the senator's wife, said the family "is encouraged and optimistic."
South Dakota's governor, elected to a second four-year term last month, has been widely seen as the Republican candidate with the best chance to challenge Johnson in two years.
Other than Rounds himself, top possibilities if a replacement senator were needed include Lt. Gov. Dennis Daugaard and state Public Utilities Commission Chairman Dusty Johnson, considered a rising star in the Republican Party. Retiring GOP legislative leaders, such as state House Speaker Matthew Michels and Senate Majority Leader Eric Bogue, also might be considered.
Johnson was first elected in 1996 and is up for re-election in 2008.
The last time the Senate convened with a perfect balance of 50 Republicans and 50 Democrats was in January 2001. Then, the two parties struck a power-sharing agreement that gave control of the Senate to Republicans but gave Democrats equal representation on committees.
Johnson, a centrist Democrat, was elected to the Senate after serving 10 years in the House. He narrowly defeated Republican John Thune in his 2002 re-election bid. Thune defeated Sen. Tom Daschle, the former Senate Democratic leader, two years later.
Daschle also visited Johnson in the hospital Thursday.
Johnson is in line to become chairman of the Senate Ethics Committee.
He underwent prostate cancer treatment in 2004, and subsequent tests have shown him to be clear of the disease.
Johnson is the second senator to become ill after the Nov. 7 election. Wyoming Sen. Craig Thomas, a Republican, was diagnosed with leukemia on Election Day. He is back at work.