Lot's of quick information on Joe Biden here, but I want you to take a look at this right now.
Biden has not spent any of his own money on his campaigns--but then again, it doesn't seem that he really has the personal finances to do so anyway, at least not compared to other members of Congress. In 2006, Biden was among the poorest members of Congress. He may have been in debt by as much as $302,980 or worth as little as $278,000 (in their annual personal financial disclosures, lawmakers report the value of their assets in ranges). In 2007, his finances didn't get any better. Last year he could have been in debt by as much as $320,980 or worth as little as $215,900. At the very least, this reduces the chance that his assets will pose significant conflicts of interest (or the appearance of conflict).
Senator Biden may not be a lower middle class or just getting by person, but he's closer to you and I than John McCain or his Vice President can ever be.
Of course, there are some things about Biden that cause some concern and I'll deal with that at a later time.