Donnelly, a former Minuteman leader who has taken a hard line on immigration and other issues in his three years in Sacramento, will focus his campaign on jobs and "civil liberties," according to a statement released by his campaign Tuesday morning.
The Assemblyman has launched recall efforts against a number of Democratic lawmakers who supported laws that place restrictions on gun owners.
The economy will also be a major issue for Donnelly, who says the state still has a "jobs crisis" that Brown has "done little to solve."
Brown is considered to be in a strong position to win a fourth and final term as governor, if, as expected, he decides to run again. He already has a campaign war chest of more than $12 million, far larger than the reserves of Donnelly or any other potential challenger.
Other Republicans considering entering the race are former Lt. Gov.