Dave Thompson, a Republican state Senator from Lakeville, is running for governor, reports Minnesota Public Radio.
The station reported Saturday night that Thompson said he plans to file the campaign fundraising paperwork on Monday, with a formal announcement planned for Wednesday.
Thompson is an attorney and former radio talk show host first elected to the Minnesota Senate in 2010. He won re-election in 2012 and currently serves as an assistant minority leader.
His timing precedes an expected announcement Sunday by Kurt Zellers, a Republican from Maple Grove, who is a former Minnesota House speaker.
Other Republicans who have announced they are in the race to challenge incumbent DFL Gov. Mark Dayton next year are Hennepin County Commissioner Jeff Johnson and Orono businessman Scott Honour.
Thompson has been mulling the race since March.
The Star Tribune has a broader look at all the candidates and their chances against Dayton.