Cynthia's comment about possible lack of future support made me a little nervous. I think I found another, albeit slightly less flexible, way to do this (called a "hanging indent"). The key is that the textindent attribute can take a NEGATIVE value. So you need to decide how far you want every line but the first to be indented, set your left margin to that amount, and then "undent" the first line by the same amount.
In pdf, which is the only destination I've tested this on, here's an example:
ods pdf text = "^{style [leftmargin=0.43in textindent=-0.43in]^{style [fontweight=bold]Notes: }This line will wrap to the word ""This"" (more text here to make this line wrap, more text here to make this line wrap, more text here to make this line wrap)}";
The nested style just bolds "Notes:". I figured out by trial and error that it takes up about 0.43 inches. I then move the left margin 0.43 inches to the right, and then indent the 1st line 0.43 inches TO THE LEFT by using a negative value. Slick, no?
Karl