Blockquote has commonly been misused as simply a way of indenting text. The problem is, blockquote should only be for making up large (usually multi-line) quotations (see its definition in HTML 4).
In CSS, simply use margin-left to achieve the same effect, like this:
margin-left: 40px;
40px is the default margin width for blockquote in most browsers. You could also use a percentage value, or em, which is based upon the size of the font (so if the user increases the text size, the margin increases too).