Less than a week ago, President Obama announced a policy change that could affect as many as 1.4 million young undocumented students living in the United States by halting their deportation proceedings and granting them temporary work permits. However, figuring out who is eligible under Obama's new policy, and how many of them exist, has been no easy task.

Pew Hispanic Center associate director Mark Hugo Lopez explained that measuring an undocumented population is inherently challenging and estimates can therefore vary widely.

"There are no surveys which ask people, 'Are you here in the country illegally or not?' And if there were, I'm not sure how reliable responses would be. So we have to rely on a number of different existing sources," Lopez told The Huffington Post.

Obama's directive will reportedly affect many of those undocumented immigrants -- often termed DREAMers -- who would have benefitted under a decade-old bill called the Dream Act, last struck down in 2010. The new policy includes those living in the country under the age of 31 who came to the U.S. as children; who don't have a criminal record; and who have served in the military, or are currently attending, or have graduated from, high school or college.

The Department of Homeland security estimated on the day of the policy announcement that nearly 800,000 individuals would be affected. However, the Pew Hispanic Center and Migration Policy Institute have independently given a number almost twice the size, projecting that nearly 1.4 million individuals will be affected.

"We're probably using some different sources and data sets," Lopez explained.

Despite numerous obstacles in measuring the population, various research organizations have begun attempts to identify who the young beneficiaries of Obama's plan are.

Nearly 60 percent of those eligible for Obama's new policy (about 800,000) are currently enrolled in K-12 institutions, a quarter of those eligible (about 370,000) are high school graduates or have earned a GED certificate, and more than 15 percent (about 220,000) are enrolled in or have graduated from college, according to recent estimates by the Migration Policy Institute.

Nearly 70 percent of beneficiaries of the new DHS directive are from Mexico, according to the Pew Hispanic Center. The remainder are likely comprised of mostly Asian and Latin American immigrants, according to a report by MPI which measured those individuals eligible for the 2010 congressional Dream Act. Jeanne Batalova, a policy analyst and demographer at the MPI, says there is significant overlap between the two populations, but that because those up to age 36 were eligible for the 2010 Dream Act, those eligible under Obama's plan are younger on average.

A quarter of those affected by the new order, nearly 350,000 young people, reside in California, according to MPI. Texas and Florida have the second and third highest numbers of eligible beneficiaries. Those eligible for Obama's new policy also tend to be from poorer families, Batalova said.

While MPI has been able to guess how many are eligible for the program, it's hard for them to tell how many will come forward, Batalova said. "At the moment it's even more difficult for us to predict how many will be affected immediately, because it's unclear who and how many will feel comfortable about stepping forward and revealing themselves to the agency," she noted.

Batalova predicts that many will not come forward until they discover if the policy will continue past Obama's first term. Presumptive GOP presidential candidate Mitt Romney has not yet announced whether or not he will overturn the policy if elected, but has set forth his own plan to allow those undocumented youth who serve in the military a pathway towards citizenship.

Myrna Ortiz, who is a youth organizer for California's DREAMer network, told The Huffington Post that her organization has brought on five interns and a small army of volunteers in order to answer calls about Obama's new policy. In the state most affected by Obama's immigration shift, the small staff can barely keep up with phone calls from DREAMers eager to apply. However, during the 60-day period in which DHS will decide the implementation specifics of the program, Ortiz says the "most important advice" is simple:

"Wait," Ortiz said. "All you can do now is wait."

HuffPost DREAMer Blog Series:

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  • Fermin Vasquez

    Fermin Vasquez serves as the statewide Communications Coordinator for Californians for Justice. One of Los Angeles' youngest emerging Latino leaders, Fermin was a Front Line Leaders Academy Fellow with the People for the American Way Foundation, based in Washington D.C. In 2010, Fermin became the first one in his family to graduate from college, and received his degree in Political Science from California State University, Los Angeles. He was also a founding member and President of Students United to Reach Goals in Education (S.U.R.G.E.), a support and advocacy organization for those that may not have come here with the right papers, but have been raised with the right values. He is a contributor to the HuffPost LatinoVoices <em>DREAMers Blog Series</em>, and his posts can be read <a href="http://www.huffingtonpost.com/fermin-vasquez" target="_hplink">here</a>.

  • Laura E. Enriquez

    Laura E. Enriquez is a doctoral candidate in sociology at the University of California, Los Angeles where she does research on the experiences of undocumented young adults. She is a dedicated scholar-activist and specializes in immigration, race/ethnicity, and gender. She has been mentoring, teaching, and organizing with undocumented young adults for the past five years. She is a contributor to the HuffPost LatinoVoices <em>DREAMers Blog Series</em>, and her posts can be read <a href="http://www.huffingtonpost.com/laura-e-enriquez" target="_hplink">here</a>.

  • Fernando Romero

    Fernando Romero is the Coordinator for the Justice for Immigrants Coalition of Inland Southern California; he is also a co-founding member of <a href="http://dreamersadrift.com/" target="_hplink">Dreamers Adrift</a>, a new media project for undocumented students, by undocumented students. He is a contributor to the HuffPost LatinoVoices <em>DREAMers Blog Series</em>, and his posts can be read <a href="http://www.huffingtonpost.com/fernando-romero" target="_hplink">here</a>.

  • Alma Castrejon

    Alma Castrejon was born in Mexico City and came to the United States at the age of seven. In 2008, she graduated from UC Riverside with B.A. degrees in Political Science - International Relations and Chicano Studies. While at UCR she founded Providing Opportunities, Dreams and Education in Riverside (PODER), a support group for undocumented students on campus. In 2011, Alma received her Master of Arts degree in Education at CSU Long Beach. She has been a member of Dream Team Los Angeles (DTLA), a community and student group that advocates for undocumented student rights and immigrant rights, since 2009; she is also an active member of Graduates Reaching a Dream Deferred (GRADD), a group of undocumented graduate students that addresses the needs of immigrant students interested in pursuing graduate education. Alma will be applying to law school in the fall of 2012. She is a contributor to the HuffPost LatinoVoices <em>DREAMers Blog Series</em>, and her posts can be read <a href="http://www.huffingtonpost.com/alma-castrejon" target="_hplink">here</a>.

  • Juan Escalante

    Juan Escalante is an undocumented student and recent graduate from Florida State University. He is a core-member of <a href="http://www.dreamactivist.org/" target="_hplink">DreamActivist.org</a> and the founder of <a href="http://dreamactivistfl.org/" target="_hplink">DreamActivistFL.org</a>; both are online organizations that provide resources for undocumented students across the country. He is a contributor to the HuffPost LatinoVoices <em>DREAMers Blog Series</em>, and his posts can be read <a href="http://www.huffingtonpost.com/juan-escalante" target="_hplink">here</a>.

  • Nancy Meza

    Nancy Meza is a human being from Jalisco, Mexico. She was brought to the U.S. by her responsible and courageous mother at the age of two and proudly grew up in East Los Angeles California. She is a graduate of Theodore Roosevelt High School in Boyle Heights. After High School she attended East Los Angeles Community College and transferred to UCLA where she became actively involved in organizing around undocumented and immigrant rights issues with IDEAS at UCLA and Dream Team Los Angeles. She graduated with a degree in Chicana/o Studies and a Labor and Work Place Studies minor in 2010. She is currently an intern at the Dream Resource Center; a project out of the UCLA Labor Center and continues to organize with Dream Team Los Angeles where she is a member of the media and communications team. She is a contributor to the HuffPost LatinoVoices <em>DREAMers Blog Series</em>, and her posts can be read <a href="http://www.huffingtonpost.com/nancy-meza" target="_hplink">here</a>.

  • Erick Huerta

    Erick Huerta is majoring in journalism at East Los Angeles College. As a member of Dream Team Los Angeles, he is one of the coordinators handling the group's communications and social media endeavors. He has lived in the U.S. for the past 20 years and has been chronicling his personal experiences as an undocumented resident for the last eight years on his personal <a href="www.justarandomhero.blogspot.com" target="_hplink">blog</a>. He's also a community reporter for the community of Boyle Heights and an avid cyclist. He can be recognized by his trademark bigotes. He is a contributor to the HuffPost LatinoVoices <em>DREAMers Blog Series</em>, and his posts can be read <a href="http://www.huffingtonpost.com/erick-huerta" target="_hplink">here</a>.

  • Jonathan Perez

    Jonathan Perez is a queer undocumented political exile from Colombia, and a Co-Founder of the Immigrant Youth Coalition in Southern California. On why he contributes to the series, he writes, "It is shocking to most, but I don't actually advocate for the DREAM Act. I organize for the rights of undocumented immigrants. I believe that in order to have meaningful changes we must first address the root causes. In order to change our realities we have to build a global movement and a global revolution. I write for the Huffington Post <em>DREAMers Blog Series</em> because it gives me the opportunity to give a different perspective to what the issues of undocumented people are." You can read his posts <a href="http://www.huffingtonpost.com/jonathan-perez" target="_hplink">here</a>.

  • Mayra Hidalgo Salazar

    Originally from Naranjo, Alajuela, Costa Rica, Mayra immigrated to the United States with her family when she was 6-months-old. She is undocumented and has dedicated her life to the immigrant movement in Florida. She lives in Lakeland, Florida where she is an organizer for Students Working for Equal Rights (SWER), a grassroots organization founded by undocumented immigrant youth in Florida. She also serves on the Florida Immigrant Coalition (FLIC) and United We DREAM (UWD) Board of Directors. She helped start an immigration legal clinic that offers free legal immigration consultation to low-income immigrants in her community and serves as the Clinic Coordinator. She also serves as the Migrant Scholar Advocate for Scaffold the Scholar, a professional development initiative for former farm-worker women working in early childhood education and is a member of the Polk County School Board Diversity Council. She was a project manager for the Trail of Dreams campaign in 2010, a 1,500 walk from Miami, FL to Washington, D.C., demanding that President Obama stop the deportation of undocumented students. Currently a undergraduate college student, she aspires to eventually earn a law degree specializing in immigration law so she can continue to serve the community that taught her to persevere against all odds.

  • Jesus Cortez

    Jesus Cortez is an undocumented graduate student at the California State University, Long Beach College of Education. He grew up in Anaheim, California and is a member of the Orange County Dream Team. He is a contributor to the <em>DREAMers Blog Series</em>, and his posts can be read <a href="http://www.huffingtonpost.com/jesus-cortez" target="_hplink">here</a>.

  • Angy Rivera

    Angy Rivera is a Colombian-born, New York-raised undocumented immigrant who started the first undocumented youth advice column, Ask Angy, while a core member at the New York State Youth Leadership Council. She also blogs for DreamActivist.org.

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