Over 20% of those without health insurance are not citizens
There's a picture here with Census Bureau figures from 2006 showing that over 20% of those without health insurance are not citizens (~46 million and ~10 million). They don't indicate what percentage of the 10 million are here legally vs. those here illegally, but surely a good percentage are illegal aliens. And, of course, illegal aliens stand a lesser chance of being counted in the Census for various reasons.
Perhaps the point could be made to those Democrats who are pushing Universal Health Care that one of the impediments to their schemes is that many Americans object to picking up the tab for foreign citizens who are here illegally, especially considering that based on their past actions both the Mexican government and their sympathizers would take steps to encourage even more Mexican citizens to come here and take advantage of our largesse. Perhaps if we worked at it we could even force the Democrats to choose between their support for UHC and their support for massive illegal immigration.