Mr. Pastor buys a Powerball lottery ticket every weekend and says he does not consider himself rich. Indeed, within the halls of Congress, where the median net worth is $913,000 and climbing, he is not. He is a rank-and-file millionaire. But compared with the country at large, where the median net worth is $100,000 and has dropped significantly since 2004, he and most of his fellow lawmakers are true aristocrats.

Largely insulated from the country’s economic downturn since 2008, members of Congress — many of them among the “1 percenters” denounced by Occupy Wall Street protesters — have gotten much richer even as most of the country has become much poorer in the last six years, according to an analysis by The New York Times based on data from the Center for Responsive Politics, a nonprofit research group…

There is broad debate about just why the wealth gap appears to be growing. For starters, the prohibitive costs of political campaigning may discourage the less affluent from even considering a candidacy. Beyond that, loose ethics controls, shrewd stock picks, profitable land deals, favorable tax laws, inheritances and even marriages to wealthy spouses are all cited as possible explanations for the rising fortunes on Capitol Hill…

With millionaire status now the norm, the rarefied air in the Capitol these days is $100 million. That lofty level appears to have been surpassed by at least 10 members, led by Representative Darrell Issa, a California Republican and former auto alarm magnate who is worth somewhere between $195 million and $700 million. (Because federal law requires lawmakers to disclose their assets only in broad dollar ranges, more precise estimates are impossible.)