Catherine Stevens has become the linchpin in the corruption trial of her husband, Alaska Sen. Ted Stevens — to both the prosecutors and his defense team.

One wants her testimony and documents to prove that the Republican lawmaker accepted pricey gifts and failed to report them. The other wants her to help prove Stevens was unaware of how much was being funneled to him by a wealthy Alaska businessman.

Defense lawyers, who said Monday she will testify this week, have painted her as the person truly in charge of the massive conversion of the modest A-frame cabin into a two-story home with wraparound decks, new electricity and plumbing, a sauna and a master-bedroom balcony.

Stevens, 84, is accused of lying on Senate forms to conceal more than $250,000 in renovations on his cabin and other gifts from Bill Allen, the former chief of giant oil services company VECO Corp. It is not yet known whether Stevens will testify on his own behalf.

The senator, who spends more time at his home in Washington than in Alaska, says he paid little attention to the project that his wife oversaw. He says he assumed the $160,000 they paid for the project covered everything.

"They have a saying in their house that when it comes to things in and around the teepee, the wife controls," defense attorney Brendan Sullivan told jurors early in the trial.

And several e-mails from Robert Persons — the next-door neighbor who served as project manager — pointedly ask the Alaskan senator to seek his wife's guidance. "Please tell Catherine that his offer of rock siding is not much of a deal," wrote Persons, who will also testify this week.

But federal prosecutors also see Catherine Stevens as key to their case, issuing subpoenas for any documents from the law firm where she works that deal with the house, the people who worked on it or anything related to her husband's case.

Defense attorneys said the firm already turned over more than 26,000 pages of documents last year, and have asked the judge to quash the subpoena.

"Especially at this late date, with the government's case concluded and the defense case already well under way, the government should not be permitted to engage in a last-minute fishing expedition to obtain broad, new discovery," defense lawyers said in a court filing Saturday.

The corruption investigation has rattled Alaska politics and made Stevens vulnerable to a Democratic challenge for his Senate seat in the Nov. 4 election. Sitting in the courtroom instead of campaigning in Alaska, Stevens has had to rely on proxies and technology to make his case to his constituents.

Almost nightly after the trial, taking advantage of the four-hour time difference, Stevens reaches out from Washington to Alaska voters, sometimes using the Internet, a technology he once described as a "series of tubes," to conduct telephonic town hall meetings to reach thousands of backers at once.

And well-known Alaska Republicans are the public face of his campaign — like former state Sen. John Binkley, who is doing television ads, and former Alaska House Speaker Gail Phillips, who is heading the campaign steering committee. "We have to carry on here to help him until he gets back," Phillips said.

But Democrats, who are running popular Anchorage Mayor Mark Begich against Stevens, aren't making it easy for the veteran lawmaker. The Democratic Senatorial Campaign Committee has so far spent more than $700,000 on ads attacking Stevens as a man no longer out to help the state, but instead assists himself and family members.

The television ads end with the tag line, "It's not about Alaska anymore" and accuse Stevens of getting federal funds for various industries, such as fishing, money that ultimately worked its way back to family members such as his son, Ben.

Stevens said he isn't worried.

"They can spend $1 million or $2 million, whatever they want to spend," he said. "But they don't have really the contact with the people that I've got."