The pauses are occasionally uncomfortable as Sen. Tim Johnson attempts to find his answer.

The South Dakota Democrat has held weekly conference calls with reporters for years, updating them on legislation and politics from the Capitol. It was during one of these calls that he had a brain hemorrhage in December 2006, almost killing him and leaving him with speech that is often slurred.

Now, as he returns to this regular routine, the reporters' updates are shorter and sometimes strained. Johnson can't always find the answer quickly, and occasionally he cuts off abruptly. Other times he sounds almost like his old self, comfortably responding with an immediate answer.

He appears to relax at the end of each call, cheerfully ending it as he did before he was stricken: "Any more questions? Going once, going twice…."

South Dakota's senior senator has been through more than most can imagine, almost dying that day 19 months ago and slowly learning to walk and speak again. His doctors and those around him often cite his remarkable recovery and mental agility, and he represents the state as he always did in Washington, not missing one vote since he returned to work in September last year.

But his disability poses challenges as he faces re-election this year.

Though his campaign against Republican state Rep. Joel Dykstra is not expected to be as competitive as his last election six years ago - when he barely beat Republican John Thune by 524 votes - he will still be expected to travel through the state, film campaign ads and participate in debates.

That could be a difficult schedule for the senator, who is still using a cane to walk - more often than when he first returned to work, when he rarely got out of his wheelchair - and can't always get the right words out of his mouth.

In Washington, Johnson has continued to bring money back to the state, using his position as an appropriator to benefit all parts of South Dakota. But he has also held back a bit more than he used to, often refraining from extended debates or questioning in committee hearings. He was not able to take the chairmanship of the Senate Ethics Committee after California Sen. Barbara Boxer had already started the job in his nine-month absence.

Johnson himself has a standard response to questions about his health.

"I've been given a second chance in life, and I want to use it to help our country and South Dakota," he often says. "While my speech continues to improve, it is still not 100 percent."

Steve Jarding, Johnson's campaign manager, says Johnson's campaign shouldn't be out of the ordinary.

"He's been able to move around when he's in the state really pretty normally," Jarding said. "The best proof for me is that he's already doing it and has been doing it."

It is still unclear, though, whether he will participate in debates.

"We are going to look at the schedule," Jarding said. "We know there are a lot of ways you can debate the issues and we'll start with that … Tim has said he would like to but nothing's set in stone."

One forum that is rapidly approaching is Dakotafest, a farm and ranch show held near Mitchell every August that has featured spirited Senate debates in the last few elections. Johnson and Thune had a pointed debate there six years ago, as did Thune and former Sen. Tom Daschle in 2004.

"We're going to see," Jarding said about Dakotafest. "I know there is some history there and we're going to take a look."

Dykstra, Johnson's GOP opponent, said he has accepted every invitation he has received to debate, including Dakotafest.

"I certainly hope that people of South Dakota will have the opportunity to see the candidates in that forum because, frankly, that's a normal part of campaigns and something that I certainly believe the South Dakota voters deserve as they are making their decisions," he said.

If the conference calls are a measure, fielding questions in a debate could be tough for Johnson.

His doctor, Dr. Michael Yochelson, says the pauses are normal for someone with Johnson's type of brain injury. While he is comfortable and more eloquent in small groups and in one-on-one interviews, a bigger crowd exacerbates his speech problems.

"If he's in a larger group where questions are being thrown at him quickly and that's much harder for him, that's typical for brain injury," said Yochelson, the director of Brain Injury Programs at Washington's National Rehabilitation Hospital. "I don't know if it's nerves or anxiety per se, it's the general volume of questions being asked and the switching of topics that make for more errors in his speech and language."

Yochelson said he and Johnson's speech therapist have worked extensively with the senator and they don't believe he is having problems with comprehension.

"Clearly in our opinion this is purely language, it's just a matter of spitting out the right word," Yochelson said. "It's not that he doesn't know what word he wants to say."

The doctor said Johnson is continuing to make strides in improving his speech and physically, unlike some patients who stop recovering after a year or so.

"Even compared to six months ago, (his speech) has continued to improve," Yochelson said.

North Dakota Sen. Byron Dorgan, a friend of Johnson's and a Democrat who works with him closely in the Senate, said Johnson is the same senator he was before he fell ill.

"Tim has been through a lot but he has come through it all and I think he's extremely effective," Dorgan said.

The Democrat's campaign is hoping voters focus on his work in Washington instead of his health.

Johnson campaign manager Jarding says the campaign will constantly remind voters of his work in the Senate Appropriations Committee, highlighting the millions of dollars he has brought back to the state - much as his campaign did in 2002.

"We have to keep focused as a campaign at looking at what is the role of a senator, and it's 'what are you doing for me lately?'" Jarding said. "For South Dakota he's doing a lot. If we do a good job and remind (voters) of what he's done, or what he's delivered, then there are going to be a lot of folks who say, 'why wouldn't we send him back?'"