HARRISBURG – In style and substance, Gov. Wolf and Lt. Gov. Mike Stack couldn't be any more different.

Where Wolf is reserved, Stack has a taste for the theatrical. Where the governor built his resume on running a multimillion-dollar family business in central Pennsylvania, Stack hails from a long-entrenched political family from Northeast Philadelphia.

Wolf comes off as studious. Stack, a card-carrying member of the Screen Actors Guild, likes to throw the political equivalent of glitter onto the staid, everyday workings of government.

The two Democrats are supposed to be a team, and next year, a political ticket. But their painfully distant, arranged marriage is on the brink.

Within weeks, the state Inspector General's office is expected to wrap up its investigation into Stack and his wife's treatment of state employees – an inquiry ordered by Wolf.

Details about the probe have been sketchy, but are said to include complaints that the couple repeatedly mistreated or verbally abused troopers assigned to protect them, as well as household staff at their official residence near Harrisburg.

Examples cited by sources -- none authorized to speak publicly about the ongoing investigation -- portray the Stacks as occasionally tyrannical and petty: an irate Tonya Stack demanding the trooper chauffeuring her in a taxpayer-funded SUV from an Eagles home game activate the car's emergency lights to clear traffic; Mike Stack, a fitness buff, sprinting out of sight from his protective detail during a run, then berating the troopers who lost him.

In a public apology, Stack has acknowledged that anger and frustration can lead to what he calls "a Stack moment." Last week, he took it a step further, calling their behavior a symptom "of a larger problem." He has declined to elaborate.

His onetime campaign manager, Marty Marks, called the problem "a deeply personal matter" for the Stack family. Marks said the 53-year-old lieutenant governor is taking actions that are "in the best interest of the health and well-being of his family," and intends to run for reelection next year.

Others close to Stack believe that Wolf's moves – asking for the probe, and then revoking the Stacks' state police protection before it is complete – are signs of a calculated political ploy. With a tough reelection campaign looming next year, they say, Wolf wants to knock out a lieutenant governor he believes is a liability.

"Some in the front office have hated him from Day One," said one longtime Capitol insider who asked not to be identified discussing the administration's inner workings, "... and went on a jihad against him."

Asked this month whether he would consider backing another Democrat next year for lieutenant governor, Wolf didn't dismiss the idea but simply said: "I haven't thought about that." He has since gone silent on the topic of Stack. "I'm not going to talk anymore about it," he told reporters last Monday.

According to Wolf loyalists, none of whom would be identified discussing intraparty issues, it was Stack who had been urged by some to consider a run against the sitting governor in next year's primary. Still, they push back on the idea that any probe into his conduct is a Machiavellian maneuver. Said one of Stack: "He's not a relevant person."

They say Wolf has been personally offended by reports of state employees being treated badly, and worried that it could lead to nasty and public litigation. Stack, they note, was warned personally several times by the governor and his office -- and didn't fix the problems.

Like Wolf, the Stacks received 24/7 protection from troopers, including a state police SUV escort. Their 2,400-square-foot residence in Fort Indiantown Gap includes a state-hired maintenance staffer and a housekeeper.

For Stack, the office was the culmination of a long but not unlikely path. His grandfather was a congressman, his father a Democratic ward leader in Philadelphia. Before becoming a judge, his mother, Felice Rowley Stack, was once a teacher --  inspired to do so to help Stack, who as a child struggled with dyslexia and attention deficit disorder, according to Marks.

Stack met Tonya when she worked as a server at an Ardmore restaurant, according to a 2014 profile in the Main Line Times. They married in 2001.

With a background in law and experience in the National Guard, Stack won his state Senate seat in 2000. But once in Harrisburg, he took a backseat to more vocal and prominent Philadelphians, including Gov. Ed Rendell, state Sen. Vince Fumo, and former House Speaker John Perzel.

Stack was not known for flowery or long-winded floor speeches, but racked up a voting record by largely standing by traditional Democratic ideals, including advocating for union protections for workers and increasing the minimum wage.

But he has long stood out in other ways. A passion for acting landed him a cameo stint as a boy in Rocky II, and later, in the Philadelphia-based John Travolta movie Blow Out. PoliticsPA.com once dubbed Stack among the state's best-dressed elected officials, noting his "particular attention to his footwear."

Though his job title has changed, that image of Stack hasn't. In the Capitol, he is often seen walking down the marbled hallway from his office on the balcony of the Capitol rotunda to the Senate chambers, where he presides over the sessions. He almost always is surrounded by an entourage of either staffers or security, his hair in place, suit perfectly pressed.

His public schedule is peppered with wreath layings, swearings-in, visits to area schools. Stack has traveled quite a bit, too, crisscrossing the state for meetings and traveling to New York, Arizona, and Quebec for conferences and events.

Contrast that with Wolf, the soft-spoken MIT grad from York County whose first action as governor was to impose a gift ban on members of his administration and who insists on taking his well-worn Jeep to and from work. He also was the man who campaigned heavily on the fact that he profit-shared with his employees while at the helm of his family's multimillion-dollar kitchen cabinet company.

"They are not even from the same planet," said Christopher Borick, a Muhlenberg College political analyst.

Wolf and Stack ran together in the 2014 general election, as required under state law, but that seemed to be where the relationship ended. Rarely do they appear together.

It's not unprecedented for governors to be estranged from their lieutenant governors. Rendell, for instance, largely kept an arm's distance between him and Lt. Gov. Catherine Baker Knoll during his tenure.

"If the governor wants to make a lieutenant governor relevant, he will," said Franklin and Marshall pollster G. Terry Madonna, a longtime observer of state government politics.

Wolf's campaign has so far kept quiet about whether or how Stack's controversy will affect them during next year's election. At least through the primary, each have his own race to run.

"I think the best case for both of them," said Borick, "is that they peacefully coexist."