Hennepin County Commissioner Jeff Johnson made it official on Sunday: He wants the state's top job.

At a news conference at a community hall in Hamel, just west of Plymouth, Johnson said he wants to replace Democratic Gov. Mark Dayton in 2014 because the state is heading in the wrong direction. "If we do not correct our course — soon — I am afraid that the greatness of Minnesota is in serious jeopardy," he said.

Johnson, 46, is the second Republican to announce his candidacy for the party's nomination. Orono businessman Scott Honour launched his campaign late last month, and several more candidates are expected to follow.

Johnson was elected a commissioner in the state's most populous county in 2008 and re-elected without opposition last fall.

Before that he served for six years in the Minnesota House before an unsuccessful statewide bid for attorney general in 2006.

Democratic officials wasted little time in weighing in against Johnson on Sunday. DFL Party chair Ken Martin called him "a classic politician trying to climb the ladder."

Hennepin County Commissioner Jeff Johnson, surrounded by family and well-wishers, announced his Republican Party candidacy for Minnesota governor at an event in Hamel on Sunday.

Johnson said that his main priorities as governor will be jobs, education and making government work. Johnson said he'll be the strongest candidate against Dayton because he's a reliable, principled conservative who can rally the Republican base and attract support from other voters, including moderates.

"We cannot win statewide in Minnesota with Republican votes alone," Johnson said. The party needs a candidate "who is actually liked by Minnesotans" who are not Republicans, he said, and "who is able to relate to the vast middle class in our state."

The Alliance for a Better Minnesota, a progressive advocacy group, on Sunday issued a statement against Johnson's candidacy. Executive Director Carrie Lucking said Johnson has a "record of extreme votes at the expense of the middle class."

Gov. Dayton has said several times that he intends to run for a second term, and that he won't actively engage potential contenders until the Republicans have decided who their endorsed candidate will be.

Tom Emmer, the party's 2010 candidate for governor, said he will not seek a rematch. Rep. John Kline and former Sen. Norm Coleman have also declined to run.

Johnson said he will abide by his party's endorsement at its state convention in June 2014, and he will not mount a primary challenge if not selected. Johnson has also been the Republican National Committeeman from Minnesota since 2011, and said he'll discontinue that role when a successor is chosen later this year.

Johnson was born and raised in Detroit Lakes and graduated from Concordia College in Moorhead and Georgetown Law School in Washington, D.C.

He lives in Plymouth with his wife, Sondi, and sons Thor, 15, and Rolf, 11.

Tom Meersman • 612-673-7388