(AP) — A Mississippi state lawmaker who nearly defeated U.S. Sen. Thad Cochran four years ago said Wednesday that he will run for the retiring senator’s open seat, but his bid to unify Republicans behind him immediately foundered.

Republican State Sen. Chris McDaniel announced that he will drop his primary challenge to incumbent Republican U.S. Sen. Roger Wicker and instead seek the Magnolia State’s other Senate seat.

Tea party supporters of McDaniel gathered at the Capitol on Wednesday to urge Gov. Phil Bryant to appoint him to Cochran’s seat when the 80-year-old senator retires on April 1.  They said the Republican legislator from Ellisville best represents their conservative views, and suggested McDaniel is owed the seat after losing to Cochran in 2014.

Instead, Bryant attacked McDaniel.

“This opportunistic behavior is a sad commentary for a young man who once had great potential,” he said in a statement.

After making his announcement Wednesday, McDaniel had urged all Republicans to rally around him and avoid a nasty primary that might give Democrats another Senate seat as the GOP seeks to hold on to its narrow majority.

“If we unite the party now and consolidate our resources, we can guarantee Donald Trump will have a fighter who will stand with him,” McDaniel said.

Hours earlier, McDaniel had told The Associated Press he remained undecided about switching. The change allows him to run for a Senate seat with no incumbent and gives him more time to campaign and raise money. While the primary against Wicker would have been June 5, Cochran’s seat is up for grabs in a nonpartisan election in November, which could be followed by a runoff.