Some of the country's most traditionally conservative states are at a greater risk of turning purple than the GOP might realize.

More than 25 million new Hispanic and Asian voters could join the electorate by 2020, according to a new study by the Partnership for a New American Economy (PNAE), an advocacy group for immigration reform. That number alone should raise an eyebrow—after all, no president in history has won the popular vote by more than 18 million ballots. But considering how many of those newly minted voters will be casting their ballots in states where the population has long voted Republican, it should also scare the GOP.

Many of those potential new voters could join because they are merely sitting idle—some 10 million Hispanic citizens and 3.6 million Asian American citizens are eligible to vote but have yet to register. Another 6.6 million Hispanics and 1.6 million Asian Americans will have turned 18, and therefore be eligible to vote. And, lastly, some 2 million Hispanics and Asian Americans, respectively, are expected to be naturalized and thus allowed to vote for the first time.

The Republican party performed poorly among both demographics in the last national election—Mitt Romney won just 27 and 26 percent of the Hispanic and Asian vote, respectively. And the party is only going to face more pressure to reverse the trend.

"I think Republicans are ignoring what are very very clear long term problems," said Jeremy Robbins, the executive director of the PNAE. "Really red states are going to be purple states really soon if the Republican party doesn't work to win over Hispanics and Asians."

Specifically, Robbins is talking about Arizona, Texas, and a few other historically conservative states, where the rise in Asian and Hispanic voting populations over the coming six years will be especially significant. In Arizona, for instance, the number of unregistered voters alone is slated to be nearly three times the margin by which Obama lost the state in 2012. In Texas, where Mitt Romney won by more than 1.2 million votes, the number of unregistered voters is roughly twice the margin of loss.

In 11 of the 18 states the study analyzed, the number of potential new Asian and Hispanic voters that will exist in 2020 either meets or exceeds the margin by which Obama lost those states in 2012.

Potential voters aren't, of course, the same thing as actual votes. Just under 50 percent of eligible Asian Americans and Hispanics voted in the last election. Depending on the percentage that vote for the Democratic party in the future, the growing pool of the two demographics could hurt the Republican party in a few key states. If the two groups vote as they did in 2012, for instance, the impact could be significant—Republicans could see almost all of their voting advantage wither away in Arizona by 2020, and about half of their lead in Texas slip away over the same period.

"The worst case scenario is a bad one for Republicans," said Robbins.

The rising number of eligible Hispanic and Asian American voters, however, could pose a much smaller threat to key red states if the Republican party works to win back those demographics' favor. In 2004, after all, George W. Bush managed to win more than 40 percent of both the Hispanic and Asian American vote.

The study's findings are consistent with a view that some GOP strategists hold, which is that ignoring Hispanics could mean never winning the White House again. Among those strategists is former John McCain senior adviser Steve Schmidt, who has said the party will need at least 40 percent of the Latino vote to win back the White House.

The importance of wooing Latino voters on the national level, however, is arguably less important than the Republican party's ability to earn them in a handful of traditionally conservative states. "The Hispanic vote could soon decide elections in places like North Carolina and Georgia," said Alfonso Aguilar, executive director of the American Principles in Action's Latino Partnership, which aims to engage Latinos in the conservative movement. "Even states like Arizona and Texas could become purple too."

Despite what appears to be a left-ward trend within the Hispanic and Asian American populations, there's reason to believe that earning a larger share of the Asian American and Hispanic vote isn't outside of the Republican party's reach.

"What people get wrong is that they assume that naturally Hispanics are going to vote with the Democratic party, " said Aguilar.

The same could arguably be true of Asian Americans. Recent polls have found that more than half of Asians—roughly 55 percent—identify with neither party, and roughly 50 percent of Latinos have cast a ballot for a Republican candidate in the past. Appealing to the issues that matter to America's Hispanic and Asian American populations could have a profound impact on how the two demographics vote in 2016, 2020, and beyond.

"I absolutely think they [the Republican party] can get back to their 2004 numbers," said Robbins. "In fact, I think they could surpass them."