Any bride may wear white. The white wedding gown is mistakenly thought to represent virginity; it in fact is merely a color of celebration (ancient Greeks wore white for their most important festivals) and a wedding fashion vogue popularized in the 19th century. Still, the second time bride might think twice about selecting the sort of "big, white gown" most commonly worn by first time bride, for fashion reasons, not etiquette reasons. If you've worn a white wedding dress before, it just seems trite to wear one again. Also, there's no getting around the widely held misconception about which brides can wear white, and so you may unknowingly be raising the eyebrows of some guests. If you've been married before, consider going for a more sophisticated, less elaborate look for your return to the alter.
The bridal veil, however, is traditionally a symbol of virginity and second time brides are encouraged not to wear a veil. At the very least, avoid wearing a blusher veil (the short piece of veil that "masks" the bride through the first part of the ceremony and then is raised by the groom when he kisses her).
See More: Gowns , Etiquette