The biggest trial in Virginia political history has turned, at times, on almost trite tales of marital dysfunction. Like the one about the busy husband, content with off-the-rack suits and slippers bound by duct tape, who watches his wife waltz in with two shopping bags and never dreams they could contain clothing worth $20,000.

With erratic wife, straight-man husband and seemingly retro spousal politics, United States of America v. Robert F. McDonnell and Maureen G. McDonnell has at times had the feel of a classic TV sitcom, just without the laughs.

At least that’s how the defense hopes it has played to the predominantly male jury that is expected to begin deliberating the fate of the former governor and first lady Tuesday.

The McDonnells have separate legal teams and are living apart, but they are united in a defense strategy that put their marriage on humiliating display. Jurors have seen the long plea the governor pecked out on his BlackBerry, begging his wife for affection. They’ve heard testimony that Maureen McDonnell was deceitful, mercurial and perhaps mentally ill.

The couple has offered up all this and more to try to convince the jury that their marriage was so broken that they were barely speaking, much less conspiring to swap the prestige of the governor’s office for $177,000 in luxury gifts and loans.

What Bob McDonnell said compared to what Jonnie Williams said.

The strategy has been a stunner coming from the McDonnells, who betrayed no hint of marital strife from the time the governor carried the first lady over the Executive Mansion threshold on Inauguration Day in 2010 to January, when they stood smilingly arm in arm at his successor’s swearing-in.

Over his long, successful career as a conservative Christian politician, McDonnell argued that there was a pressing public interest in strengthening traditional marriage. Today, as a criminal defendant, McDonnell has a compelling personal need to declare his 38-year union all but dead.

“They had been the most publicly affectionate first couple I’d seen in 30 years,” said Bob Holsworth, a former Virginia Commonwealth University political scientist who has attended the trial almost daily. “You’d see them at public events, hand in hand, very often arm in arm, for almost the entire evening.”

The defense pairs its broken-marriage narrative with an argument that the rich businessman who showered the McDonnells with gifts and loans got nothing from the governor beyond political courtesies commonly extended to donors, such as setting up meetings with top state officials.

Prosecutors contend that onetime Star Scientific chief executive Jonnie R. Williams Sr. got more than that. The McDonnells hosted what prosecutors characterize as a product-launch party at the mansion for Williams’s dietary supplement, Anatabloc. The first lady touted the pills at large conferences. And the governor appeared to nudge his top legal counsel via e-mail to find out why two state medical schools had not moved ahead with studies Williams wanted on Anatabloc’s active ingredient.

The defense has argued that if the help provided to Williams ever crossed the line, that was the sole doing of a first lady who was suckered by a slick salesman, desperate for attention and powerless to offer official favors in her own right. And her estranged husband, the argument goes, was utterly in the dark.

Regardless of whether they create reasonable doubt, the theatrics leavened a trial that bogged down at times with arcane detail. Drowning in the minutiae of financial transactions and cellphone records, the jury of seven men and five women could grab on to a colorful “difficult wife” narrative.

The perks of politics

Gov. McDonnell has received over $300,000 in gifts since 2002. See all politicians and donors.

Records show McDonnell was aware of his family’s most substantial financial transactions with Williams. Those include a $15,000 payment to cater a daughter’s wedding, a $50,000 low-interest loan secured in 2011 and two other loans worth a total of $70,000 that the governor personally negotiated in 2012.

McDonnell has tried to explain those ties in terms that make his wife the heavy. He said he was “astounded” to learn about the first $50,000 loan that his wife secured when Williams was a near-stranger. He said he wanted her to give it back, but because she was so difficult, he lacked the emotional energy to fight her on it.

“I just needed to pick the battles with my wife on certain things very carefully,” the ex-governor testified.

The strategy has the potential to backfire with jurors, who might conclude that McDonnell is unfairly throwing his wife under the Ferrari that Williams famously lent them.

McDonnell’s decision to move out of the family house in suburban Richmond shortly before trial could likewise cut both ways. The former governor testified that he was staying with his priest during the trial because he couldn’t bear to rehash the day’s events every night with his wife.

Jurors could hear that as confirmation that Maureen McDonnell is, indeed, hard to be around and that the marriage is on the rocks. But they could also see McDonnell’s move in terms unflattering to him: The man who professed regret that public service had so often kept him apart from his wife has left her alone again at a moment of profound need.

Even so, the broken marriage defense could help Maureen McDonnell as much as her husband. Because the role of first lady is ceremonial, her lawyers have asked the judge to instruct jurors that she cannot be convicted of selling official favors directly. If the judge agrees — he will issue instructions Tuesday — she could be convicted of corruption only if the jury concludes that she conspired with her husband, the office-holder. If jurors conclude that anything inappropriate was done by Maureen McDonnell without her husband’s knowledge, they could both wind up off the hook on those charges.

That would still leave bank-fraud charges related to applications that did not list loans from Williams as liabilities. And an obstruction charge for Maureen McDonnell, who after being questioned by investigators returned dresses to Williams along with a note hinting they had always been loaners.

Prosecutors have suggested that the McDonnells, who have come and gone from court each day separately but walked into pretrial hearings hand-in-hand, might be faking estrangement. And the state of the marriage is irrelevant in any case, prosecutors argued, because the couple clearly communicated about loans from Williams.

“No one — absolutely no one — knows the happiness of that marriage other than the two people sitting over there,” Assistant U.S. Attorney Michael Dry said in closing arguments Friday. “But we do know one thing: It does not matter.”

But Henry “Hank” Asbill, a McDonnell defense attorney, called the couple’s marriage “the terrible tragedy at the heart of this misguided prosecution.”

“It may be unpleasant. It may be uncomfortable,” he told jurors. “But you now have to evaluate the relationship.”

The professed marital discord contradicts the tight-knit family image projected since 2009, when McDonnell ran for governor on a campaign bus shrink-wrapped with an image of the couple and their five children. He entered political life with the professed goal of using public policy to bolster marriage and the family, two institutions he saw in precipitous decline.

“As the family goes, so goes the nation,” concludes the Regent University master’s thesis he penned in 1989, two years before his first election. Among other things, the thesis called for the creation of “covenant marriage,” which would be more difficult than conventional unions to dissolve through divorce. It also bemoaned the rise of working women and feminism as “detrimental” to the family.

When the thesis surfaced during his 2009 campaign, McDonnell dismissed it as an “academic exercise.” Yet some of the domestic scenes described at trial suggest he has held on to the traditional view of himself and other men as head of the household — even as he elected not to exercise his authority at times to keep the peace with his wife.

Musing on his newlywed daughter Cailin and her husband in the context of the wedding Williams helped bankroll, McDonnell testified: “As a dad, this was a man who was going to take care of her the way I had taken care of her when she was a little girl.”

Asbill said one of McDonnell’s mistakes was a failure to rein in his wife, describing him as a “weak husband” who could have found “more forceful or creative ways to correct mistakes or temper her anger.”

The trial has shown flashes of a thoroughly modern Maureen McDonnell. She chafed at the idea that her career, selling Nu Skin products from home, had to play second fiddle to her husband’s. But more often, the Maureen-ran-amok defense has painted a portrait of McDonnell as an old-fashioned, hen-pecked husband.

And then there are the moments that any long-married person could relate to, despite particulars steeped in gubernatorial grandeur.

There was the testimony of the young lovers whose “couple time” is eventually lost to kids, carpools, and the whirlwind schedule of a big-state governor and 2012 vice presidential prospect.

There’s yelling over something small — what the wife will wear on a big day — while the overworked husband fields phone calls. Here, the day in question is the one after McDonnell won the governor’s race. And on the other end of the line: the president of the United States.

There is bickering over who gets credit for accomplishing something — a second $50,000 loan. Maureen McDonnell complains that she landed it and that her husband merely swooped in at the end to work out the terms.

“I worked on this loan 4a year, not Bob,” Maureen McDonnell griped via text to her sister-in-law in 2012.

Now more than ever, she wants that credit. And her husband needs her to have it.