If every undocumented immigrant had cast a vote for President Obama in 2012, he would have won Arizona, Georgia, North Carolina and Texas, and he would have beaten Mitt Romney by nearly 11 percentage points nationally, instead of three.

Only citizens can vote, however, and 11.2 million unauthorized residents didn't get the chance.

But with immigration overhaul on the table, legalizing new Democratic voters looms as a threat for conservatives who don't want to hand their political foes a potential windfall of 11.2 million new voters with the creation of a pathway to citizenship -- and to voting rights -- with a comprehensive bill.

"The fear that many people have is that the Democrats aren't interested in border security, that they want this influx," Rush Limbaugh griped during his Tuesday interview with overhaul champion Sen. Marco Rubio of Florida. "For example, if 70 percent of the Hispanic vote went Republican, do you think the Democrats would be for any part of this legislation?"

New immigration policies could mean in influx of new voters, but Republicans needn't worry about it in the short term. See Also: Gang of Eight Accelerates Immigration Reform Pace

"Under almost any scenario, it's pretty far in the distance," Jeff Passell, senior demographer at the Pew Hispanic Center, said of the prospect that unauthorized immigrants' gaining voting rights would pump up numbers significantly enough to meaningfully change the U.S. electorate.

And yet, the "influx" wouldn't be negligible: "Realistically, we're talking about potentially adding probably 5 million potential voters or so in 10 years," he said.

Hispanic voters broke 71 percent for Obama in November, and Republican strategists recognize that the party has failed to court Hispanic voters effectively. But depending on how slowly the citizenship line moves, the Republican Party will have a decade or so to shake its anti-Hispanic stigma.

See also: A Glossary for Immigration Reform

"It's a long time coming. You're talking about 15 to 20 years before we're talking about a whole slew of new voters coming into the electorate," said Jennifer Korn, executive director of the Hispanic Leadership Network, who served as Hispanic outreach director for George W. Bush's presidential campaign.

"If Republicans can map out and change their positions with things that Hispanics do support -- on less government, lower taxes, less regulations on small businesses -- then they can really compete for the Hispanic vote over the next 20, 30 years."

There are 11.2 unauthorized immigrants living in the United States, according to the Pew Hispanic Center's estimate. While most are of voting age (Pew estimates just 1 million younger than 18), the deluge of new Democratic voters might not be as substantial as Limbaugh implied.

In other words, it's not as if Democrats will gain 11.2 million votes in the next few years. Here are some things to keep in mind:

  • Not All Hispanics Vote for Democrats. Most do, but not all, and voter preferences vary from state to state. In Florida, 60 percent of Hispanic voters backed Obama, according to 2012 exit polls; in Arizona, 74 percent voted for the president. Even if all 11.2 million had voted in 2012, Obama would only have picked up North Carolina if they simply hewed to Hispanic voter trends. Romney still would have carried Arizona, Georgia and Texas, although he would have won Georgia by less than 1 percentage point. (Note: There were no exit polls in Texas or Georgia, and here the national rate provides rough estimates of how results would have changed.)
  • Not All Naturalized Citizens Vote. Not everyone votes, period, and naturalized citizens vote less frequently. In 2008, 64 percent of the voting-age population voted, according to the Census Bureau. Data from 2008 show that naturalized citizens voted almost as frequently, at 63.6 percent, but only 54.2 percent of naturalized Hispanics votes.
  • Income Can Matter, a Little Bit. Median household income for unauthorized immigrants was $36,000 in 2007, according to Pew. The $30,000-$39,999 bracket turned out slightly less than the total electorate in 2008, according to the Census Bureau, at a rate of 62.2 percent.
  • No Swing States Will Flip, Yet. The Hispanic population is expected to continue growing in the next several decades, and demographic shifts in the electorate, at this point, are assumed. But if all 11.2 million undocumented immigrants had been able to vote in 2012, it's unlikely they would have turned any presidential states blue. Granting 60 percent turnout -- higher than the 54.2 percent for naturalized Hispanics in 2008 -- Obama would have picked up 102,000 votes in North Carolina, but Romney would have picked up 46,500, and the net gain of 55,500 votes for Obama wouldn't put him over the top, even in the one state most likely to have turned blue with newly legal immigrants voting.
  • Not Everyone Will Naturalize. It's impossible to tell how many of the 11.2 million unauthorized immigrants will gain citizenship and become eligible to vote, and it depends on how difficult the process will be. Immigration overhaul is still in its nascent stages, far from the details of what paperwork, waiting periods, probationary statuses and fees unauthorized aliens will have to pass through on their way to the voting booth.
  • Unknown: House Effect. Presidential politics are easy to figure, but voter trends get more interesting in House races. And not much is known about where, specifically, undocumented immigrants live. The Pew Hispanic Center would only categorize them as largely "metropolitan," meaning the undocumented population is concentrated in cities and suburbs.

    But with heavy congressional-district gerrymandering in Southwestern states such as Texas, where Republicans control the state legislature, it's possible newly legal voters will fall in districts that are already heavily Democratic by design, as Republicans have cordoned off the deepest pockets of blue in congressional redistricting.