It appears that WordPress supports no customizations to ordered lists.
The HTML attributes "type" and "start" are stripped from any code I enter, e.g.:
<ol type="A" start="3"></p>
would have the "type" and "start" attributes stripped.
I realize that "type" and "start" are deprecated attributes, so I tried the list style CSS properties, e.g.:
<ol style="list-style-type: upper-alpha";</p>
These all work beautifully in blogger and other environments and I'm at a loss to understand why these attributes and CSS properties would be stripped in WordPress.