A plumber of 12 years who demostrated concern to Obama since he wanted to purchase his plumbing business which made more than $250,000/year, and would thus be subject to higher taxes under Obama's tax plan. He claimed that the increase in taxes stopped him from pursuing the business since he wouldn't be able to afford his workers. In the third presidential debate, McCaine referenced Joe the Plumber to express how Obama's tax reform will affect small business owners like Joe. This caused a lot of media attention towards "Joe the Plumber", and Joe Biden recently expressed his lack of concern towards "Joe the Plumber" by saying most plumbers do not make $250,000/year.
Joe the Plumber is an example of how middle class citizens will be affected by Obama's tax plan, but he makes up for a minority of small business owners-- according to Obama, 98% of small business makes less than $250,000/year