Various historical accounts, as well as novels and films, portray noble, but impoverished British families forced to endure marriages with wealthy merchants and capitalists in order to preserve the manner to which they have grown accustomed. The marriages are usually portrayed as a quid pro quo: the nobles get money, the gentry get titles for their children/grandchildren.
Was there a similar push by wealthy Americans/Canadians to marry into noble European families -- and was there a difference between the American and Canadian outlook as Canada was still part of the Empire? If so, how were these efforts looked upon by British and European nobles vis a vis their own gentry, and just generally? Further, how did they work out for the North Americans?
Many wealthy Americans have married a title, particularly and most notably during the "gilded age" at the end of the 19th century, when the "new" American moneyed society desired to burnish their pedigree with the trappings of European nobility. This included famous families like the Astors and Vanderbilts. Winston Churchill was himself the result of just such a marriage - his mother was American heiress Jennie Jerome.
Reactions from European society ran the full spectrum. Some regarded the trend as an invasion of barbarians diluting the better classes, some saw it as a necessary infusion of fresh blood, and every opinion in between. Popular opinion was the same, ranging from contempt to fairy-tale romanticizing. As for how it worked for the Americans, that's a case-by-case basis. Some heiresses became quite popular and accepted by European society, some did not. The families did purchase some patina of social credibilty, but whether that was worth the price is a personal judgment, I think. Coming into the modern world, I personally feel that their money would have spoken just as loud in society without a pedigree as with.
A recent book "Old World, New World" by Kathleen Burk (British) goes into quite a bit of detail on this subject. She's a bit too favorable to the trend for my tastes, but the information seems sound. Also, there's a modern, if imperfect, example of the phenomenon out there. Actress Jamie Lee Curtis (herself kind of Hollywood "royalty") is married to Actor/Director Christopher Guest, who is actually the Baron Haden-Guest of British peerage. However, the example is imperfect because, as I understand it, this was more a case of "now that we're getting married normally, I should tell you that I'm a Baron" as opposed to marrying for a title. Anyway, she was far more famous than him when they wed - she didn't really need a title that is the tenth most interesting thing about Spinal Tap's guitarist.