INDIANAPOLIS (AP) -- Indiana Rep. Luke Messer is formally announcing that he will challenge Democratic Sen. Joe Donnelly in 2018.
The Republican congressman previously formed a finance committee and was widely anticipated to run. But he waited until Wednesday morning to announce the bid on Twitter.
Donnelly is considered one of the most vulnerable Senate Democrats in 2018. Republicans have signaled they will spend considerable sums to retake the seat previously held by former Sen. Dick Lugar.
But already the GOP primary is looking like it could be brutal. Messer and fellow Republican Rep. Todd Rokita have traded insults for weeks.
Rokita has yet to formally announce his candidacy but has hired key campaign staffers for an expected Senate bid.
Senator Joe Donnelly's campaign manager released the following statement after Messer announced his run:
"Joe Donnelly has been an independent voice for Indiana in the U.S. Senate. Hoosiers know that Joe will always put them first - not party bosses, corporate lobbyists or special interests in Washington. Ranked by the Lugar Center as the second-most bipartisan member in Congress, Joe's no stranger to rolling up his sleeves and reaching across the aisle to get things done to keep good-paying jobs in Indiana, protect our service members and veterans and combat the opioid epidemic ravaging our state. Despite Congressman Messer's entry into the Republican primary, there's still only one person on next year's Senate ballot who is deeply connected to the Hoosier electorate and has a proven track record of working across party lines to deliver for Hoosiers, and it's Joe Donnelly."
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