There’s a reason why House Speaker Paul Ryan, R-Wisc., holds the leadership position he does today.

It’s because back in the fall of 2015, when former House Speaker John Boehner, R-Ohio, announced his resignation, House Majority Leader Kevin McCarthy, R-Cailf., couldn’t muster the necessary votes to succeed the Ohio Republican and clasp the Speaker’s gavel.

Republicans went scrambling. Ryan said he didn’t want the job. And after two weeks of coaxing and guilting, the Wisconsin Republican accepted the challenge.

Ryan’s now retiring in early January. It’s unclear if Republicans will hold the House after the midterms. That could make a race for the Speakership moot. But it speaks volumes that some lawmakers and observers believe House Majority Whip Steve Scalise, R-La., could leapfrog McCarthy in the GOP leadership hierarchy.

This is a leadership melee that was delayed by two-and-a-half years when Ryan grudgingly took the Speaker’s job and helped Republicans sidestep an internecine bloodbath. But the deferred tumult could unfold now.

McCarthy may not have been well-positioned to succeed Boehner in 2015. But he’s bolstered his credentials since then and improved his standing among House Republicans compared to a few years ago. Plus, McCarthy’s tight with President Trump.

No one quite thought Scalise had the bona fides to climb much higher in the GOP ranks recently.

But the Louisiana Republican literally took a bullet for the team at a baseball practice last June. After multiple surgeries, Scalise’s health has improved. The Whip is walking more with braces, no longer relying exclusively on a motorized scooter to navigate the Capitol. Support for Scalise isn’t just out of pity or sympathy. It’s because Scalise’s resilience and fighting spirit has captured the imagination of the GOP rank-and-file.

“There is no leadership election,” said McCarthy Wednesday as a phalanx of reporters chased him across Statuary Hall and into the House chamber. “Paul is Speaker right now.”

But Scalise’s ambitions are clear.

“I’ve been interested in moving up,” said Scalise to Fox. But Scalise adds, “we can’t start some crazy leadership race now.”

That may be true. But retirement announcement at this point in the spring does nothing but animate the leadership vortex.

On one hand, Ryan’s departure was the worst-kept secret in Washington. It was generally thought that Ryan had little to gain by hanging around as Speaker after Congress approved the tax reform law.

The Speaker clashed sometimes with President Trump and tried to inoculate himself and House Republicans from the president’s tweets and rhetorical haymakers.

After adoption of the $1.3 trillion omnibus spending bill last month, many political handicappers suggested Ryan may struggle to win the Speaker’s race should Republicans hold the House.

Some also wondered if Ryan could find himself in a Democratic tidal wave back home. Ryan represents a district which only favors Republicans by five percentage points in a battleground state.

Ryan’s enhanced profile as Speaker also makes him a target.

However, only two House Speakers have ever lost a general election: Speaker Tom Foley, D- Wash., in 1994 and Speaker Galusha Grow, R-Pa., in 1862.

A source familiar with the Speaker’s thinking dismissed suggestions that Ryan’s decision to bow out were connected to the Speaker’s race or the ballot box in Wisconsin.

“Anything to do with holding onto the gavel was not part of the conversation,” said the source. “It was clear he was going to win re-election.”

It was slightly surprising that Ryan announced his intentions now, not after the election.

That sprays political propane on a possible leadership skirmish which may not be resolved until Thanksgiving at the earliest and early January at the latest. Republicans won’t pick their candidates for Speaker (if they hold the majority) or other leadership posts until a few weeks after the midterm elections. A vote for Speaker won’t unfold on the floor until the first week of January.

"I think it is good that everything is put off until after the election,” said Rep. Pete King, R-N.Y. “The last thing we need now is a leadership election.”

But not everyone agrees with King.

“I don’t think it will be ignored until November,” said Rep. Mark Meadows, R-N.C., leader of the conservative House Freedom Caucus. Meadows told reporters the Freedom Caucus has the votes to “veto” a possible Speaker or leader. Meadows and other Freedom Caucus members claimed Boehner’s scalp in 2015. President Trump may also play a role tapping a Ryan successor.

“Certainly for (President Trump) to weigh-in is appropriate,” said Meadows.

Ryan, McCarthy, Senate Majority Leader Mitch McConnell, R-KY, and Senate Majority Whip John Cornyn, R-Texas, headed for the White House for a pre-scheduled dinner with Trump Wednesday night. But Scalise was invited to the banquet late.

Multiple sources noted it was only appropriate to summon Scalise to the banquet, considering the events of the day. Other sources suggested some may have accused the White House of favoring McCarthy had the administration not included Scalise.

But again, it’s significant that people are monitoring the semiotics of the White House meal. That tells you a leadership race is on – even if it’s not.

Former Senate Minority Leader Harry Reid, D-Nev., announced his retirement in early 2015.

Senate Minority Whip Dick Durbin, D-Ill., has long held the number two position in the Senate Democratic Caucus. There were rumblings about Sens. Patty Murray, D-Wash., and Elizabeth Warren, D-Mass., matriculating. But current Senate Minority Leader Chuck Schumer, D-N.Y., locked down the votes to succeed Reid within hours – even though the formal leadership vote was a year-and-a-half away.

Nothing is settled among House Republicans.

“I am throwing my weight 100 percent behind conservative principles,” said Rep. Dave Brat, R-Va., when asked by Fox who he supported. “I think it is a mistake to make it about horserace stories or personalities.”

“I am not going to vote for anyone who voted for this omnibus bill,” declared Rep. Thomas Massie (R-KY). “How could you be serious about cutting costs when you vote for an omnibus like that?”

No one has officially declared for anything – including McCarthy and Scalise. There’s even a theory that McCarthy would likely have the votes to be Minority Leader if Republicans lost the House. But the theory says Scalise could command enough support to be Speaker if Republicans retained control of the House following the midterms.

Still, a couple of dark horses bear watching: Reps. Mark Walker, R-N.C., and House Resources Committee Chairman Rob Bishop, R-Utah. Walker chairs the Republican Study Committee, the largest bloc of conservatives in the House. Bishop presided over the Utah House in the mid-1990s as Speaker.

Over the years, Ryan’s frequently described how his own father would down Canadian Club daily after work and passed away when the Speaker was 16. Lots of people say they’re quitting politics to spend more time with their family. But mindful of what happened to his own father, that may really be the case for Ryan. The Speaker says his kids only see him on the weekend.

Fox is told the Speaker’s day began Wednesday as it often does, with a vigorous workout in the House gym. But something was different for Ryan Wednesday. The Speaker usually exercises until about 7:40. But Wednesday, Ryan wrapped up at 7:10. He had to tell the leadership team, top aides, members of the Wisconsin Congressional delegation, Trump and Vice President Pence of his plans to step down. A source says that the Speaker seemed particularly at peace Wednesdays and “happy.”

As Ryan showered, word came via Twitter that John Boehner was joining the board of Acreage Holdings to help legalize marijuana to combat the opioid crisis and conduct research. Boehner’s announcement was hardly the biggest Speaker-related news of the day.

Ryan may have filled the void created by Boehner’s abrupt departure in 2015. Boehner groomed former House Majority Leader Eric Cantor, R-Va., to succeed him. But then Cantor unexpectedly lost his 2014 primary to Dave Brat. The post-Boehner leadership crystal ball clouded up ever since. That’s why some tribalized fighting is starting now.