The throne of France is an interesting subject, and a tricky one, since one must go back hundreds of years to the Treaty of Utrecht. Later, when the Comte de Chambord died in 1883, many Frenchmen turned to the Comte de Paris, grandson of Louis Philippe. Others turned to Don Juan de Bourbon (Spain), Chambord's brother-in-law, and Head of the House of Bourbon until his own death in 1887. Chambord's widow, Marie Therese of Austria-Este, opposed the Orleanist claim.
Today, this issue is rather moot, as the French throne is almost certainly gone for good. I am not an Orleanist. Neither do I support the young Duc d' Anjou. If one is a strict royalist, Anjou is the product of a morganatic union, since his mother had no royal or noble blood in her. And how he, himself, has married a commoner. In the past, this would have disqualified him from the throne (as was the case with the descendents of the Habsburg Franz Ferdinand in Austria. If he had lived, he would have become Emperor, but his children by Grafin Sophie Chotek(spelling?) were entirely disqualified). By the way, the Duc d'Anjou's father died in a tragic skiing accident in the U.S. in 1989----he was nearly beheaded.
On the other hand, the Orleans family has the terrible legacy of the Duc d'Orleans, who voted for the death of Louis XVI, and Louis Philippe, who usurped the throne in 1830. However, if one is holding to the strict letter of the law according to the 300-year-old Treaty of Utrecht, the current Comte de Paris has the clearest claim to the French throne today.
Since we're discussing thrones and marriages and bloodlines, let's not forget that the current heir of the Spanish throne, the son of King Juan Carlos, married a commoner. So that royal line has been diluted (actually, it was severely diluted by Isabella II, none of whose children were the offspring of her husband/cousin--who was nicknamed "Fanny" and almost certainly homosexual).