Not identity theft, but copyright and trademark infringement, assuming of course the Angle camp was smart enough to copyright and trademark their relevant sections. The federal identity theft statutes deal primarily with the unauthorized transfer or duplication of a "means of identification of another person". That isn't this.
Unfortunately, even with the appropriate copyrights, the Courts have given WIDE birth with respect to political satire and parody. Unless there are some violations of campaign finance laws - and that's possible as they're wildly complicated (and I'm not very familiar with them), then Angle probably doesn't have a very strong legal case against Reid, or whomever did it.
Well, that wouldn't apply. There is absolutely no "satire" or "parody" involved.
The Dims' entire point is that Angle is (supposedly) "scrubbing" her previous views and endorsements in her new website. So their explicit and stated purpose is to put up the original Angle website just as it existed before, at least as far as the about, positions and endorsements pages.
They've copied the original Angle website, and basically reposted it under the auspices of "The Nevada State Democratic Party."
Who will she sue next? The Wayback Machine internet archives? They have copies of all her pages going back to 2004.
Nothing ever dies on the internet. I hope she and her people understand that.