Utah Attorney General Mark Shurtleff has made up his mind about whether to challenge fellow Republican Sen. Bob Bennett — but still won't say publicly what he'll do.

"I've made my decision," Shurtleff said in a brief interview with the Deseret News on Friday.

Shurtleff has hinted at a 2010 run for Senate for months, postponing and postponing again any announcement — mostly because his wife is resisting the idea.

"That's why it's taken so long," Shurtleff said. "I kind of decided some time ago, but you have to involve the family and my wife asked for a month to talk me out of it. We've had a lot of talks."

But Shurtleff was coy about whether that meant he was going to run for the Senate.

"I'm 99 percent sure what I'm going to announce," he said. "But that's why I'm waiting another week."

Shurtleff has scheduled a May 20 news conference to announce his intentions in the 2010 elections, once he returns from a trade mission to Israel with Gov. Jon Huntsman Jr.

Bennett has been preparing for the possibility of a challenge from Shurtleff. In an interview with the Deseret News in March, he said he had begun organizing when Shurtleff's name first surfaced as a potential challenger in February.

"Of course, as long as he delays making his final decision we will continue to be even more ahead of that," Bennett said. "The fundraising is going very well."

Bennett held a fundraiser in April where he hosted former Salt Lake Olympics boss and one-time GOP presidential candidate Mitt Romney, raising about $225,000 for his campaign war chest. Shurtleff recently held a fundraiser himself, taking on the topic of the Bowl Championship Series.

Apparently perceiving Shurtleff as a serious threat, Bennett initially sought to have Shurtleff be a co-chairman to his campaign, something that the attorney general "demurred," he said. Asked if he has heard of any other Republicans expressing interest in the race, Bennett indicated Shurtleff is the biggest name to surface.

"I've heard some other names rumored, but my sense of it is that Shurtleff being so public, he's probably scared most of them off," he said. "I haven't heard the names of anybody who is capable of putting together a credible statewide organization. He's been elected three times statewide, so he has some understanding of it."

Contributing: Lee Davidson. E-MAIL: bwinslow@desnews.com