Written in 4/4 in a single major key with no changes, and no bridge it is a truly unique popular song. Even the melody is based on a simple pattern of 3 descending notes.
The A section is sparsely worded, establishing the expectation of the standard AA'BA pattern song, in the predictable I, IV, I, V, harmonic progression heard in a million other pop songs.
"Screen door slams, mary's dress waves"
The song continues to the A' portion with lyrics setting a syncopated rhythm that is Springsteen's signature style, and holding the listener's ear while the song continues thru the same chords as the first.
"don't you run back inside, you know what i'm here for"
The B section is what you would typically expect to be the bridge but stays in the same Major key as the A section using borrowed 5ths and substitutions:
I, vi, I, IV, I, iii, IV,"You can hide neath the covers and study your pain-
Make crosses of your lovers and throw roses in the rain"
But instead of using the turnaround to lead back into another A section, it repeats the B section entirely
"Well I'm no hero, that's understood..."
Where Springsteen has brought someplace new in a pop song. we no longer know what we are going to hear next.
The next section begins like the A section, but instead of I, IV, I, V; he substitutes the V for the iii;
".. these two lanes will take us anywhere"
He continues IV, V. So the progression goes
I, IV, I, I,The thwarted expectation of another A section sets up a kind of harmonic tension, as it looks for resolution in the next verse, which is also denied as it moves into a B section.
I, iii, IV, IV
IV, V, I, IV
IV, I, V, V
"Oh oh, come take my hand"
The song could very well end at this point, but doesn't as a totally new C section is added.
IV, V, I, I"Well I got this guitar and I learned how to make it talk."
vi, V, I, I
IV, V, iii, vi,
IV, ii, V, V
Which repeats again.
"There are ghosts in the eyes of all the boys you turned away."
The final section defies all expected patterns bouncing around until it finds the final cadence IV,V,I.
IV, V, V, IV"This town's full of loser, and we're pulling out of here to win"
iii, iii, IV, IV
ii, V, IV, ii
IV, IV, V, I
By breaking out of the familiar pattern, it is able to sound interesting and fresh in spite of it's simple progressions by using the dense lyrics which at times spill out of their measures and run into one another. therefore, relying heavily on Simple of I, IV, V chords in a single major key isn't as much of a problem as the choice of which measure among the four in each phrase seems to fit the loosened structure, and becomes like an accentuated beat.
Thunder road's genius is in its simplicity.
