Ray Wylie Hubbard Channels Flannery O'Connor.

This entire song by Ray Wylie Hubbard is shot through with Flannery-esque images and languages.  In fact, it would not be too much of an exaggeration to say that this song constitute a sort of Cliff Notes to Flannery O'Connor's two novels (Wise Blood and The Violent Bear It Away).  But there are images here that are very like ones in O'Connor's short stories as well.
Let's look at the evidence:

1.  The very opening line of This River Runs Red is:

My mama run off with a Bible salesman.

This is remeniscent of Flannery's story Good Country People, in which the ugly but intellectual proto-feminist farmgirl Hulga is courted by a traveling Bible salesman.

2.  Hubbard continues,

My mama's mama took me in to save me from sin, the kind she said sweet Jesus died for.

This is remeniscent of the teenage years of Enoch Emery, Hazel Motes' foil in the novel Wise Blood.  Enoch was raised by a foster mother with hair so thin that it "looked like ham gravy trickling over her skull".  He eventually prays to Jesus for a way of escape from this woman.

3.  Hubbard's grandmother wants to get him baptized, which is the main story line in the song, as well as in O'Connor's The Violet Bear It Away, which has at its center a sort of Fundamentialist-style ex opere operato view of Baptism, which results in the simultaneous drowning and  baptism of a retarded child, Bishop.  Hubbard's first reference to Baptism is:

Before the next sunrise, gonna get you Baptized.

4.  But just as Hazel Motes (Wise Blood) runs away from his fiery religious upbringing, Hubbard's character is not able to keep on the straight-and-narrow way:

Now I got baptized that Sunday morning.
I guess it didn't take, as I look back.
'Cause when I turned fifteen, I just seemed to get mean,
And I stole my mama's mama's Pontiac.

5.  The "just seemed to get mean" line is very remeniscent of Onnie Jay Holy's sermon in Wise Blood, regarding how a child's sweetness doesn't show so much as he reaches his teenage years.

6.  The car is significant, too.  For although Hazel Motes did not steal his rat-colored Essex automobile, the theft of the grandmother's Pontiac in Ray Wylie Hubbard's song is completely consistent with Hazel's philosophy:  "Nobody with a good car needs to be justified."

7.  When Hazel runs away to "the city", he takes up with a prostitute named Leora.  Hubbards character moves to Tulsa and takes up with a woman named Lorraine.

8.  But run as they will, both Hazel Motes and Hubbard's character are perpetually haunted by their childhood religious upbringings in general, and by their Baptisms in particular.  The blind preacher Asa Hawks notes of Hazel that some preacher has left a mark (the mark of Baptism) on him.  He is haunted, but cannot erase the mark.  In a similar way, Hubbard's character cannot forget his Baptism:

Now it happens every night when they turn out the lights, I can't stop the voices in my head:
'This river runs red, this river runs red, This river runs red like Jesus' blood.'