[/nq] All I can tell you is that the Random House Historical Dictionary of American Slang records it in use since 1894, with the meaning "to ask for money, to beg" and so forth. " I rather doubt you'll do much better than that. There are thousands and thousands of words that have slang or colloquial meanings, particularly in combination with other words, and the reason for each formation if it was ever known was never recorded.
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