Utah Attorney General Mark Shurtleff (R) launched his 2010 primary challenge to three-term Sen. Bob Bennett (R) on Wednesday at a press conference at the Utah Capitol building.

He also sent the announcement to his supporters via Twitter.

“Time to stop the bailouts. Just launched my campaign for US Senate & restore fiscal responsibility in DC,— Shurtleff wrote. “Please donate at markshurtleff.com.—

In recent months, Shurtleff — who won a third term as attorney general last year and isn’t up for re-election until 2012 — has criticized Bennett for being a key Republican voice during passage of the $700 billion Wall Street bailout bill last October. Considering the strong conservative backlash against that piece of legislation, some Utah Republicans have said Shurtleff might gain traction in a primary if he successfully paints Bennett as a Washington, D.C. insider.

A National Research poll of 300 likely primary voters conducted earlier this month for Shurtleff showed the two men would begin the race in essentially a dead heat. Shurtleff also held a rating of 78 percent favorable to 6 percent unfavorable. Bennett’s rating was 74 percent favorable to 19 percent unfavorable. The poll had a 6-point margin of error.

That poll was in the field before Bennett’s camp launched an ad featuring former GOP presidential candidate Mitt Romney — whose family has strong ties to the state and who is extremely popular there — expressing his support for Bennett.