By Bush Family, you mean his parents. I believe the reason he attends St. Johns is because of its convenience to the White House, and they are very used to having Presidents and other dignitaries in attendance there. I don't think he thinks of himself as an Episcopalian or a Methodist; that is my impression. I think Evangelical Christian is the applicable term in his mind, which you mentioned.
"The Bush family is Episcopalian,.." ~ RobbyS
The 55 Framers of the Constitution (from North to South):
John Langdon, Congregationalist (Calvinist)
Nicholas Gilman, Congregationalist (Calvinist)
Elbridge Gerry, Episcoplian (Calvinist)
Rufus King, Episcopalian (Calvinist)
Caleb Strong, Congregationalist (Calvinist)
Nathaniel Gorham, Congregationalist (Calvinist)
Roger Sherman, Congregationalist (Calvinist)
William Samuel Johnson, Episcopalian (Calvinist)
Oliver Ellsworth, Congregationalist (Calvinist)
Alexander Hamilton, Episcopalian (Calvinist)
John Lansing, Dutch Reformed (Calvinist)
Robert Yates, Dutch Reformed (Calvinist)
William Patterson, Presbyterian (Calvinist)
William Livingston, Presbyterian (Calvinist)
Jonathan Dayton, Episcopalian (Calvinist)
David Brearly, Episcopalian (Calvinist)
William Churchill Houston, Presbyterian (Calvinist)
Benjamin Franklin, Christian in his youth, Deist in later years, then back
to his Puritan background in his old age (his June 28, 1787 prayer at the
Constitutional Convention was from no "Deist")
Robert Morris, Episcopalian, (Calvinist)
James Wilson, probably a Deist
Gouverneur Morris, Episcopalian (Calvinist)
Thomas Mifflin, Lutheran (Calvinist-lite)
George Clymer, Quaker turned Episcopalian (Calvinist)
Thomas FitzSimmons, Roman Catholic
Jared Ingersoll, Presbyterian (Calvinist)
John Dickinson, Quaker turned Episcopalian (Calvinist)
George Read, Episcopalian, (Calvinist)
Richard Bassett, Methodist
Gunning Bedford, Presbyterian (Calvinist)
Jacob Broom, Lutheran
Luther Martin, Episcopalian, (Calvinist)
Daniel Carroll, Roman Catholic
John Francis Mercer, Episcopalian (Calvinist)
James McHenry, Presbyterian (Calvinist)
Daniel of St Thomas Jennifer, Episcopalian (Calvinist)
George Washington, Episcopalian (Calvinist; no, he was not a deist)
James Madison, Episcopalian (Calvinist)
George Mason, Episcopalian (Calvinist)
Edmund Jennings Randolph, Episcopalian (Calvinist)
James Blair, Jr., Episcopalian (Calvinist)
James McClung, ?
George Wythe, Episcopalian (Calvinist)
William Richardson Davie, Presbyterian (Calvinist)
Hugh Williamson, Presbyterian, possibly later became a Deist
William Blount, Presbyterian (Calvinist)
Alexander Martin, Presbyterian/Episcopalian (Calvinist)
Richard Dobbs Spaight, Jr., Episcopalian (Calvinist)
John Rutledge, Episcopalian (Calvinist)
Charles Cotesworth Pinckney, III, Episcopalian (Calvinist)
Abraham Baldwin, Congregationalist (Calvinist)
William Leigh Pierce, Episcopalian (Calvinist)
William Houstoun, Episcopalian (Calvinist)
William Few, Methodist