Let’s time-hop to around this week four years ago, when the magazine Mother Jones surfaced a video of Mitt Romney disparaging the “47 percent” of Americans who — he claimed — do not pay any (federal) income tax.

There are 47 percent of the people who will vote for the president no matter what. All right, there are 47 percent who are with him, who are dependent upon government, who believe that they are victims, who believe the government has a responsibility to care for them, who believe that they are entitled to health care, to food, to housing, to you-name-it. … These are people who pay no income tax. Forty-seven percent of Americans pay no income tax.

The presidential candidate was grandstanding for a crew of wealthy donors. But even in that context, the remarks sounded awkward. They revealed how Romney and his cadre of campaign consultants had misjudged the GOP coalition of 2012.

The Republican business leaders wanted lower taxes and less restrictive government, as always; but the growing populist wing demanded more tangible solutions for the middle and lower-middle class. Four years ago, these groups were bound together by a fragile line of reasoning that threaded notions of personal responsibility and racially coded condemnations of welfare recipients.

But the truth is that a significant proportion of Republicans receive government benefits of one kind or another. They rely on Social Security or the Earned Income Tax Credit, or food stamps or TANF, or Medicaid. Not only did the gaffe make Romney seem cruel and disconnected, but his remarks insulted the Republicans who are in the 47 percent. It's a complicated relationship. Many regard themselves as hard-working citizens who have been forced against their will into the embraces of the social safety net.

Now, in 2016, polls suggest that Donald Trump's supporters are heavily concentrated among the same “47 percent” that Romney dismissed four years ago.

Arlie Russell Hochschild, a University of California sociologist, has written incisively about the rise of the populist right and their champion. Trump, she argues, “solves a white male problem of pride.”

Unlike some other Republicans, Trump doesn’t stigmatize government assistance programs. In the division between “makers” and “takers,” he legitimizes being a “taker.” He accomplishes this, Hochschild says, in part by shifting the scrutiny to other groups, such as immigrants and Muslims. For instance, when Trump claimed (incorrectly) that the welfare system helps undocumented immigrants more than it benefits “native American” households, the subtext was that his own supporters are among the deserving recipients of government assistance.

In Trump’s view of the world, the problem isn’t welfare, necessarily. It’s that welfare goes to the wrong people.

Hochschild's observations lend some context to the results of a new study from economists Don Fullerton, of the University of Illinois, and Nirupama Rao, of New York University. Fullerton and Rao analyzed data from a long-term research project that has followed the fortunes of over 18,000 Americans since 1968.

They found that there is significant churn among those who don’t pay the federal income tax. The so-called “47 percent” are not some permanent underclass of dependents. A large fraction of them quickly get back on their feet again.

“The tax system is providing insurance,” Fullerton said. “In good years you're paying income taxes. But if you have a bad year — say you get laid off — you get a break from the government.”

Before digging into the data, it’s worth recognizing that the real figure is somewhat smaller than 47 percent. Romney took that figure from a Tax Policy Center estimate for 2009, a year when many Americans were still reeling from the recession. In more typical times, the data suggests that about 39 percent of American households don’t pay the income tax in a given year.

Of those households, about 18 percent started paying taxes the very next year. Five years out, about 40 percent of them have begun earning enough to pay the tax. Who are the rest? Some of them are students and retirees (in the data, about half of people over 55 did not pay income tax in a given year). And some, of course, are the chronically poor.

But as this chart from the paper shows, few people escape the income tax for very long. Of those who have ever been part of the 47 percent — or rather, the 39 percent — most of them do end up paying the income tax for most of their lives.

There is nothing necessarily wrong, by the way, with not having to pay income tax. It is exactly why we have a progressive income tax in the first place: to take pressure off people who don’t have the means to contribute at the moment. Most people pay other forms of taxes anyway — payroll taxes, sales taxes, gas taxes, and so on.

A much smaller fraction, about 10 percent of Americans, receive assistance from the government in the form of food stamps or TANF or unemployment benefits. But again, most of them quickly cycle off benefits. The drop-off is quite steep. Of the people who receive some form of government transfer in a given year (other than Social Security), about 44 percent of them stop receiving it the next year. Only about 20 percent of them receive benefits for five straight years.

As this chart shows, of all the households in the data that ever receive government transfers, about 30 percent of them take the government money only for a single year.

Although few people are receiving government benefits at any given moment, many more will do so at some point in their lives, the economists say. In the data, about 58 percent of households in their data received benefits at least once in the past, and 68 percent did not pay income tax for at least one year. This is evidence, Fullerton says, that the social safety net is serving its function.

“The point is that these welfare programs don’t induce a culture of dependency,” he said. “There are short-lived programs.”

The statistics that Fullerton and Rao highlight reveal a truth that may seem self-evident not only to Trump supporters, but to middle-class Americans of all stripes. Welfare and public assistance don't only serve the desperately poor. These are relatively broad programs that will touch most lives in this country.

As for the people who don't pay any income tax — they're not "takers"; they're average Americans. The "47 percent" has a vast alumni network. More likely than not, most of us will join that club one day.