(CNN) -- Republican presidential candidate Newt Gingrich recently declared his support for a "path to legality" for undocumented immigrants who have been in the U.S. for longer terms, have paid taxes and have strong family and community ties.
"If you've been here 25 years and you got three kids and two grandkids, you've been paying taxes and obeying the law, you belong to a local church, I don't think we're going to separate you from your family, uproot you forcefully and kick you out," Gingrich said at the recent CNN debate on national security.
It turns out that might not include a lot people.
A study released this week by the Pew Hispanic Centers estimates that there are currently 10.2 million unauthorized adult immigrants in the United States, of which two-thirds -- or roughly 6.8 million -- have been in the country for at least 10 years.
Of that 6.8 million, about 3.5 million of them have lived in the United States without authorization for 15 years or more and around 2.8 million have been here between 10 and 14 years.
Interestingly enough, Gingrich singled out immigrants who came to the U.S. illegally at least 25 years ago: That corresponds to those who were here around 1986. That was the year President Ronald Reagan signed into law the controversial "amnesty" bill that legalized the status of 1.7 million immigrants.
At the time the law was passed, there were about 5 million illegal immigrants in the United States. Today there are twice as many. The Pew study could not determine how many of those immigrants were here 25 years ago yet didn't take advantage of the amnesty law.
The Pew report, authored by Mark Lopez, associate director of the Pew Hispanic Center, and colleagues Jeffrey Passel and Seth Motel, was based on U.S. Census Bureau's 2010 Current Population Survey and paired with the Pew's own analysis. The report also showed that 22% of undocumented immigrants have been here between 5 and 9 years. Only 15% of those immigrants arrived in the last five years.
The sharpest growth in the immigrant population, according to the report, occurred in the 1980s and 1990s. That inflow, however, has slowed significantly in recent years as the U.S. economy has sputtered and border enforcement has tightened. In addition, the report documented the fact that relatively few long-duration illegal immigrants have returned to their countries of origin.
About half of undocumented immigrants -- roughly 4.7 million people -- are parents of minors, in sharp contrast with the 38% of legal residents and 29% of all U.S. born adults who are parents.
The report also indicated that unauthorized immigrants are, on average, younger than the rest of the population and have more children.