[enuddleyarbl]

I've gone a similar route, but with div classes:

div.poem {
/* Poem Styling */
	display: block;
	font-size:	.88em;
    font-style: italic;
	margin-left:	2em;
	margin-right:	2em;
	padding-left:	1.5em;
	text-align:	left;
}
div.poem p {
/* Poem Paragraph Styling */
	display:	block;
	margin-top:	0;
	margin-bottom:	0;
	text-indent:	-1.5em;
}
div.poem p.first {
/* Poem First Line */
	display:	block;
	padding-top:	1em;
}
div.poem p.indented {
/* Poem Entirely Indented Stanza */
	display:	block;
	margin-left:	2em;
}
div.poem p.last {
/* Poem Last Line */
	display:	block;
	padding-bottom:	1em;
}

The padding-left in the base poem class gives me more of a block-indent.