There were four distinct audience groups Thursday night when President Barack Obama delivered a prime-time address about immigration policy and his go-it-along program to reform it.

The first audience group tuned in to the Spanish-language Univision Network, which delayed the second half of its live production of the 15th annual Latin Grammys to cover Obama’s speech.

At least 9.8 million viewers tuned in to all or part of last year’s Latin Grammys, and a significantly larger audience tuned in Thursday — which means Univision defeated CBS, ABC, Fox and NBC in ratings. And for good reason — for the millions of immigrants who watch Univision, the smallest details of Obama’s plan will be life-altering.

The second group, opponents of Obama’s executive order, likely watched the speech on Fox News expecting to feed on conservative commentary poking holes in the president’s unilateral process. The pundits say Obama has been prodding Congress for more than a year to fix a broken immigration system because his own authority to act is limited by the Constitution. More than one critic quoted Obama’s “I’m not the emperor of the United States.”

They say Obama has reversed course and is acting like an emperor.

The third group, Democrats and liberals still faithful to a lame-duck president who is forced to govern alongside a Republican House and Senate, were tuned in to the left-leaning MSNBC, where a more sympathetic line of commentary drew parallels between Obama’s order and the actions of past presidents — Eisenhower, Kennedy, Johnson, Nixon, Reagan and both Bushes all took unilateral action to make immigration changes by relying on their executive authority.

The fourth audience was, for the most part, left out. They were blissfully watching “Bones,” “The Biggest Loser” or “Grey’s Anatomy.” The major networks — ABC, CBS, NBC and Fox — did not broadcast the speech because the White House never formally asked them to, according to The Washington Post. So anyone who identifies with the vast mainstream — the very voter who two weeks ago repudiated Obama’s party and his agenda — and was interested in watching was probably tuned in to CNN.

These demographic realities reflect what’s likely to be a major complication in any Republican effort to counter Obama’s executive order. By focusing on the Univision audience, and specifically on the Latin Grammys audience, Obama targeted and connected with an exclusive segment of the population without a substantial risk of alienating other population segments.

Any criticism thrown to the mainstream masses might seem overblown when many of the masses missed the speech that’s being criticized.

And any legislative proposal for immigration reform from the GOP Congress will be perceived not only as late but also a hindrance to Obama’s initiative — an initiative necessitated by six years of inaction on the part of Congress.

That’s the likely perception, whether it’s true or not, and in the political arena perception is reality.

That’s a reality the GOP-controlled Congress will have to live with, at least through the last two years of Obama’s term.