One month before the voters pull levers and punch ballots, key events in the personal timelines of Barack Obama and Mitt Romney are still hazy, and unnecessarily so. It’s not exactly news that, as a Mormon missionary in France, Mitt Romney willed himself back to life after a car accident in which a police officer wrote Il est mort on his passport. It’s also a known known that President Obama’s relationship with his mother was so distant that he didn’t thank her in his high school yearbook, but offered gratitude to his grandparents — and to Ray, “a hippie who could get them the good stuff,” according to biographer David Maraniss.

The Washington Post reporter is among the various journalists, columnists, biographers and other original sources who chime in and add authority to “The Choice 2012.” This election-year, PBS “Frontline” franchise excels at surfacing and synthesizing the personal details that make the partisan clash more of a human story. The producers blend news clips, vintage video and in-person interviews to construct dual portraits that find their own rhythm, like a political junkie’s remix.

The clever juxtaposition of video makes the men more vivid. In one montage, college-age Romney counterprotests anti-Vietnam War protesters at Stanford; looking like the eldest boy on “My Three Sons,” he scowls at his peers. Fifteen years later, and just down the California coast, there’s Obama, grinning in indelible photos on the campus of Occidental College, where his mahalo vibe is evident behind mirrored shades.

These Frontline political documentaries are awards magnets that have garnered Emmys and Peabodys and a Pulitzer, if not major audiences. They are assiduously fair, if rarely artful. They lean hard on archival footage — like, in “The Choice,” Harlem street scenes during Obama’s years at Columbia, or Fanueil Hall replays of Romney’s debates and bill signings. The visuals are thus a step up from C-SPAN, but in visual language that is, above all, trustworthy.

Michael Kirk, the show’s guiding hand, never steers toward either candidate, but also spares neither. What’s seen as the Republican nominee’s goody-goody nature is dissected, along with his wealth and resistance to persistent questioning. During a private meeting in Boston a half-dozen years ago, Iowa GOP powerbroker Douglas Gross dared to ask the sitting governor about his anticipated liabilities, as seen by Iowans: “Mormon, Massachusetts, multimillionaire.” According to Gross, both Mitt and Ann Romney bristled at what proved to be a prescient question.

Obama is presented as unfailingly “laid back,” even when that quality propels him toward failure. Commentators show how his refusal to fit any stereotype let’s him stay above the political fray. When he becomes editor of the Harvard Law Review, he is quick to say his inclusion means the disadvantaged will have a new voice in an exclusive forum. But we hear from his liberal, African American classmates how they were shunned as Obama instead courted conservative peers. It’s among several moments that suggest “his intense desire to avoid being trapped,” a theme offered by Maraniss.

The show’s narrative arc suggests that the men’s religious beliefs are tied to their political aims. By many accounts, when Obama joined his wife Michelle’s church, religion helped build his place in politics. For Romney, his political aims mean much to his church. A Mormon historian explains that a win for Romney could be seen as “an act of consecration,” and that “it would certainly be a great accomplishment in building the Kingdom on Earth.”

In the parallel stories, neither man fits in easily with the groups he is supposed to represent, and both suffered Election Day wallops when they made their first moves toward Capitol Hill. Obama is accused of being “not black enough” to represent Chicago’s South Side, and Rep. Bobby L. Rush (D-Ill.), the ex-Panther, mocks Obama for having “more degrees than a thermometer.” On the other hand,Obama eventually had to explain away his Chicago pastor, the Rev. Jeremiah Wright, in the run-up to the 2008 election.

When the story shifts to Romney, viewers see how he began as an independent, and then, running as a Republican in Massachusetts, he sounded very much like a Democrat on the issues of abortion, climate change and equality for gays and lesbians. It was a set of beliefs so fluid that the late Sen. Edward M. Kennedy (D-Mass.) mocks him for not being pro-choice but “multiple choice.” Then, and again in presidential runs as his party’s standard-bearer, Romney rarely satisfied the party faithful, and evangelicals have harbored doubts about whether Mormonism was Christianity, Gross explains.

Astute viewers will make their own comparisons, ones that aren’t explicit in the deep-toned narration of Will Lyman. From the start of his career, Romney is shown focusing on wealth, while Obama focused on poverty. Raised by grandparents who each struggled with alcohol, Obama found an extended family in his Hawaiian toker’s club, the Choom Gang, and later, in college, through a multi-culti array of international students. In contrast, Romney is a teetotaler, as his faith dictates. And by marrying young and multiplying, he has stuck close to a family ideal that his parents reinforced, not just to him, but also to voters in Michigan and nationwide, as the clean-cut family took so often to the campaign trail.

Their fathers are shown to loom extra-large. After Harvard, Obama eschewed corporate law and clerkship opportunities to write a book about his absent Kenyan father. In doing so, he probed his itinerant life after his mother followed her new husband to Jakarta. A classmate from Obama’s Hawaii years recalls his boyhood boasts that he was Indonesian royalty and would return there to rule. (He later revised the tale to make Kenya his future fiefdom.)

In one loop, a boyish Romney giggles in front of cameras, testifying that his favorite car is the Rambler, a pioneering product of American Motors, the company George Romney led. When Mitt makes it to Harvard Business School, the academics have a new vision for corporate America, toppling “buddy-buddy” institutionalists like his dad. And according to a pair of magazine profilers, Romney approaches politics the way a management consultant evaluates a company’s problems. All decisions are dictated by numbers, not relationships or ideology.

Under Kirk’s direction, each presidential candidate is revealed as upstanding — and stand-alone. They are figures who reshaped the restrictions of their birthrights, and demonstrated that they were going to succeed in ways their fathers didn’t. Each is a notorious grind, and through a two-hour toggle between their biographies, viewers can see how the gears in their brains turn, in very different directions.

“Frontline: The Choice 2012” airs on PBS stations at 9 p.m.