McDaniel spokesman Noel Fritsch said that the lawsuit will be filed in Jones County, Miss., according to the AP.
The state senator's legal team announced last week that they would definitely file a legal challenge. McDaniel claimed that he actually won the primary runoff by 25,000 votes.
On Monday, McDaniel's legal team sent a list of the allegedly irregular votes as preliminary notification to the Cochran campaign. Among the votes voluenteers tallied, they included McDaniel's own lawyer and his lawyer's wife on the list of irregular votes.
McDaniel asked supporters to help fund his legal costs in a Wednesday letter, according to the Clarion-Ledger.
"Our case is a strong one," he said. "This fight won't be easy, and it won't be cheap. So I'm asking you to chip in $50 or more to help us fund this fight."
According to the Clarion-Ledger, once McDaniel's lawyers file the challenge, the Mississippi state Supreme Court chief justice will appoint a judge to hear the case, who will then decided where to hear the challenge.