A conservative insurgent pushed the Republican Party closer to another explosive war with itself by positioning himself Monday to launch a campaign for the Senate.

Mississippi state Sen. Chris McDaniel announced that he would hold a rally on Wednesday — a platform he could use to announce a bid for either of the two Senate seats he has been eyeing.

“I’m going to be holding an event, and I think you can probably read between the lines as to why I would be holding an event,” McDaniel said, hinting at an announcement without explicitly saying what it would be.

The possibility of a challenge against Sen. Roger Wicker, or perhaps a bid for Sen. Thad Cochran’s seat, put party officials on edge. Hours ahead of his comments, which came in a Facebook Live event Monday, speculation was rampant among Republicans about what he would say.

Some predicted he would take on Wicker. Others ventured he might target Cochran. Even those closest to him were reluctant to make concrete pronouncements about his plans.

Whatever McDaniel decides will probably have a direct impact on the Republican Party well beyond the state’s borders. His hostilities toward party leaders have made him a threat to the establishment. His far-right views have spurred fear among some GOP leaders that he is a liability in the general election.

McDaniel has been plotting a return to the big stage since Cochran narrowly defeated him in 2014 in one of the nastiest Republican primaries in recent history. He has been looking at challenging Wicker, who is up for reelection this year, or Cochran, who is 80 and has suffered health problems.

The deadline for candidates to file to run against Wicker in the GOP primary is Thursday. The incumbent has been preparing for a contested primary for months, stockpiling cash and aligning himself with President Trump in an effort to appeal to conservative primary voters.

On Monday, Wicker released two new television ads that allies noted were meant as warning shots against McDaniel. One features a state legislator who was supportive of McDaniel when he ran in 2014 but now backs Wicker.

In his remarks on Facebook, McDaniel laid the groundwork for a campaign against the status quo in the GOP. He said he thought that “most conservatives feel that our party, the Republican Party, has lost its foundation.”

He added that he thinks the party “is no longer rooted in something steady and something sure.”

McDaniel said his Wednesday event would be at Jones County Junior College in his home town of Ellisville, Miss.

For months, Republican officials in Washington and Mississippi have been bracing for Cochran to retire from the Senate, even though he has not said he will do so. McDaniel told a member of Republican Gov. Phil Bryant’s inner circle in mid-October that he was interested in being appointed to Cochran’s seat if Cochran were to retire or die before his term expires after 2020, according to two people familiar with the situation.

Bryant has indicated that he is not interested in doing that. Trump and Senate Majority Leader Mitch McConnell (R-Ky.) have urged Bryant to consider appointing himself, according to multiple people familiar with the conversations.

Much of the maneuvering around Cochran reveals an attempt to box out McDaniel, who favors replacing McConnell as Senate leader, among other controversial positions. McDaniel supported the presidential campaign of Sen. Ted Cruz (R-Tex.) in the 2016 primaries.

If Cochran were to resign this year, it would prompt an interim appointment from the governor and trigger a special election for the seat, to be held on Nov. 6. There would be no primary under Mississippi’s rules for a special election, but a wide open general election in which candidates, Republicans and Democrats, would vie for a majority of the vote to avoid a runoff.

Names mentioned in Republican circles as potential appointments include Agriculture and Commerce Commissioner Cindy Hyde-Smith, Lt. Gov. Tate Reeves and Secretary of State Delbert Hosemann.

Those Republicans, contacted directly or through representatives, did not immediately respond to inquiries Monday about their plans.

Republicans close to the situation have predicted privately that Cochran could step down — or at least make an announcement about leaving — as soon Congress finalizes a long-term government spending agreement. For Cochran, the chairman of the powerful Appropriations Committee, such a moment could offer a chance to go out on a high note.

But Cochran has not said he will leave. Brad White, Cochran’s chief of staff, said Monday that Cochran “hasn’t given me any announcement to make” about retiring before the end of his term, which expires in January 2021.

Congress has given itself until March 23 to finalize and pass its spending plan. Government funding will dry up after that.

Clay Chandler, a spokesman for Bryant, said, “Mississippi is stronger because of Senator Cochran’s service, and I look forward to it continuing. Speculation about anything else is insensitive, irresponsible and unfair.”

McDaniel has told The Washington Post in recent months that he is looking at both Senate seats, as well as a run for lieutenant governor of Mississippi.

McDaniel’s future could have a direct bearing on the battle for the Senate majority. Republicans hold a 51-to-49 majority, giving them little room for error.

Already this election cycle, they have had to deal with a devastating loss in a deep red state. Democrat Doug Jones defeated Roy Moore in Alabama, flipping a longtime Republican seat after revelations that Moore had been accused of making unwanted sexual advances to teenage girls when he was in his 30s.

Since then, the insurgent wing of the party has tried to regain some momentum, while mainstream Republicans have pointed to Alabama as an example of what happens when candidates who are not thoroughly vetted are nominated in key contests.

Michael Scherer contributed to this report.