Obama's plan

Obama's anticipated plan is expected to include relief from deportation for millions of immigrants. The new program is likely to build on the Deferred Action for Childhood Arrivals (DACA) program from 2012, which allowed young immigrants who would have benefited from the DREAM Act to apply for two years of protection from deportation, and for work permits.

The plan's also going to include other elements, including further tweaks to immigration enforcement and a plan to expand legal immigration. But relief for unauthorized immigrants is the centerpiece — and the most controversial element.

Here's what we know the White House is considering, and what looks likely to make it into the final package.

How many people could be covered?

Estimates tend to be on the order of about 4 million, based on a New York Times report. Those 4 million newly-eligible immigrants would join the 1.2 million unauthorized immigrants who are currently eligible for the Deferred Action for Childhood Arrivals program (DACA), making a total of 5 million unauthorized immigrants who'd be eligible for relief once the plan goes into effect. (It's worth noting that only about half of those eligible for DACA have actually applied for protection from deportation, so how many immigrants are eligible doesn't necessarily equal the number who are protected.)

It all depends on who exactly is included in the new program, which no one knows for sure at this point.

Which types of immigrants could be covered?

The president's ability to protect unauthorized immigrants from deportation is supposed to be limited to particularly worthy cases. When the Obama administration instituted the DACA program in 2012, they justified it by saying that they were limiting the program to a particular group of immigrants — and then using the application process to evaluate individual cases.

Similarly, for this round of immigration relief, the administration will probably carve out one or more groups of unauthorized immigrants who will be eligible to apply, and then set an additional set of criteria that individuals in those groups will have to meet to get their applications approved.

Here are the groups that are most likely to be eligible under a new program:

Unauthorized immigrants whose children are US citizens or green-card holders. There are 3.5 million unauthorized immigrants with US-citizen children (in most cases because their kids were born in the US). These immigrants should be eligible for legal status themselves, after their children turn 21. But they're blocked by rules that make it extremely difficult to get legal status in the US if you've ever been unauthorized — especially if you're not willing to risk leaving the US in the hopes that you might get to come back. Another 150,000 immigrants are parents of green-card holders, and would have to wait even longer — assuming their children didn't become citizens — to get legal status in the US.

Unauthorized immigrants who came as children or teenagers — who aren't already protected from deportation. In 2012, Obama created the Deferred Action for Childhood Arrivals program, which was intended to protect young unauthorized immigrants who would have qualified for the DREAM Act. The DACA program is limited to immigrants who arrived before 2007, and who were under the age of 30 when the program was announced. Expanding the program to older immigrants who arrived in the US as children, or to immigrant children and teenagers who arrived after 2007, could protect up to 300,000 more immigrants from deportation.

Jeanette Vizguerra, a Colorado immigrant whose children are US citizens and who's been fighting her deportation.

Here are a few other groups that haven't been mentioned in recent reports about the administration's plan — or about whom there are mixed reports:

Possibly included: Unauthorized immigrants who are married to US citizens or green-card holders. There are 1.5 million unauthorized immigrants in the US whose spouses have US citizenship, or at least a green card. They should be eligible for legal status immediately, but are blocked by the same rules that make it so hard for unauthorized immigrant parents to get legal status. These haven't been mentioned in any reports yet, though there have been vague reports of other immigrants being protected "by other means."

Uncertain of inclusion: Farmworkers. Historically, legalizing unauthorized farmworkers has been more popular with Congress than legalizing other unauthorized workers — a bill called "AgJOBS," to grant legal status to farmworkers, has been floating around Congress as long as the DREAM Act. On Wednesday, Politico reported that farmworkers weren't being included in the administration's plan — but the United Farm Workers claimed that 250,000 farmworkers would be protected from deportation.

Probably not included: Other unauthorized immigrants with children. The Obama administration has said that immigration enforcement shouldn't split up families, and advocates believe that the only way to guarantee that is to protect parents from deportation. There are 900,000 unauthorized immigrants whose children are not citizens, but are under 18. The administration could also protect the parents of DACA recipients, which could cover several hundred thousand more unauthorized immigrants. But according to Politico, lawmakers who attended the Wednesday dinner with President Obama said that DREAMers' parents would not be included.

What other requirements would an immigrant have to meet?

Immigrants won't automatically qualify for legal status if they fit one of these categories. There are other criteria to consider as well. To qualify for DACA, for example, an immigrant has to meet a set of criteria regarding age, education, criminal record, and time in the United States. Not all of those will matter for other groups of immigrants (age requirements will likely be dropped) but others will.

In particular, the administration is expected to require applicants to have been in the US for a certain number of years before they're eligible for relief. The DACA program required immigrants to have been in the US since at least 2007 — five years before the program went into effect. (That's why the current proposals include a plan to expand it to other immigrants who arrived as children after 2007.) By that standard, an estimated 3.3 million parents of US citizens or green-card holders would be eligible.

The question is whether the White House will say that immigrants have to have been in the US for five years to be eligible for the new program, or whether it will require them to have been here for ten years. The higher standard could exclude 800,000 parents of US citizens or green-card holders. Furthermore, it's going to be extremely hard for immigrants to prove when they entered the country without papers.