An imposing and impressive lead performance somewhat atones for an awkwardly structured script and a charisma-starved supporting cast in “A Great Awakening,” the new film biography of the 18th century English preacher who lent The American Revolution some of his values and forward-thinking turns of phrase like — the film suggests — like “All men are created equal.”

Jonathan Blair of “Found on South Street” has the vocal and physical presence to put over the rock star appeal of Anglical pastor turned ardent revivalist George Whitefield, who founded the evangelical Christian movement during his British and American preaching tours that popularized “The Great Awakening” of the 1700s.

He is remembered by the aged Benjamin Franklin (John Paul Sneed, who was “Covenant Rider” back in the ’90s) as he and his printer/grandson Benjy (JT Schaefer, making his film debut) rummage through old copies of Franklin’s “Pennsylvania Gazette” during a break in the fractious and quarrelsome Constitutional Convention of 1787 in Philadelphia.

Seeing Whitefield’s name and writings and sermons among Franklin’s mementos, Benjy is told “George Whitefield WAS the Revolution!”

The story then flashes back to working poor Whitefield’s childhood interest in acting, his work study arrangements that got him into Oxford and his meet up with men of faith who put the idea in his head that with his voice, he’d make a fine pastor and an even better “preacher.”

We see his rising zeal, his attempts to fast his way to Godliness in the manner of Christ (“It almost killed me.”), his soaring popularity as a preacher who attacked not just sins but injustice and a hidebound, dull Anglican liturgy.

He was an Anglican outcast and star before he ever came to America. When he arrived, his tour was as heralded as the later British Invasion pop stars, with the not-remotely-Anglican Franklin becoming his “partner” in publicity, selling thousands of newspapers, a shrewd journalist and marketer hyping the preacher’s vast crowds (We see Franklin calculting an educated guess, one that’s larger than the population of Philadelphia).

But the film does a middling job at tying this religious figure to The Revolution and revolutionary thought.

I can find no reference to Whitefield using the “created equal” phrase, which predated him and Thomas Jefferson, who made it famous in the Declaration of Indepedence.

The clumsily-organized script (no opening credits or “title” to reassure you that you’re in the right theater) hints at a complicated life of protest against the “dead preachers” of the Anglican Church hierarchy, of a man who chastised the American South for its rationalization of “slavery” and who then owned slaves to run a Georgia orphanage he founded and financed, but also — the movie leaves this out — later lobbied Georgia to legalize, accept and embrace slavery.

The film’s squishy agenda thus feels like an attempt to shoehorn in a religious figure as a spiritual “founding father” amongst all those landed gentry humanists like Jefferson and outspoken deists like Benjamin Franklin. The movie implies that evangelical zeal both inspired the revolt and — thanks to Franklin — motivated the later Constitutional Covention.

Divine intervention created the Electoral College?

As a preacher who plunged into ministering to the poor, the incarcerated and the enslaved Whitefield would open his sermons with thunder and brimstone.

“AWAKE, oh sleeper! The Son has Arisen!”

That’s about as “woke” as a preacher gets, for those looking to rationalize Christian nationalism.

Blair stands out in the cast, but this is a pretty inexperienced lot in front of the camera, and it shows.

Director Joshua Enck (“I Heard the Bells”) and his crew give the film a polished look — Whitefield “crossing” to America in a period-correct sailing ship, and convincing streets, prisons and what later came to be called “Independence Hall,” where the state representatives bickered over small-state/big state, free-state/slave state issues add to the film’s credibility.

But seeing Franklin take Whitefield out kite-flying in a thunder storm is trite, and it’s not the only scene that plays that way.

Accounts of “The Great Awakening” may focus on the man and his works and contradictions. But series like “The American Revolution” barely touch on that phenomena setting the stage for revolt. Perhaps that’ll change. But it will take a better movie than “A Great Awakening” — perhaps also starring Blair — to make that case, back it up with facts and make it stick.

Rating: PG-13, violence

Cast: John Paul Sneeds, Jonathan Blair, Alana Gerlach, JT Schaefer and Russell Dean Schultz.

Credits: Directed by Joshua Enck, scripted by Jeff Bender, Jonathan Blair and Joshua Enck. A Sight & Sound Production released by Roadside Attractions.

Running time: 2:09