This article is from the archive of our partner National Journal

If Republicans are to take the White House in 2016, they will need to win over more Latino voters than strategists have typically estimated.

According to an analysis by the polling firm Latino Decisions, the Republican presidential candidate will need the backing of between 42 and 47 percent of Latino voters to win the presidency. For the past several presidential elections, the assumption has been that Republicans needed to reach 40 percent.

"The 40 percent figure is no longer reliable," said Matt Barreto, cofounder of Latino Decisions and one of the authors of the new report.

That's because the size and makeup of the Latino electorate is shifting.

The changing demographics of this country, specifically the growing share of Latino voters, mean that the percentage of Hispanic voters the candidates will need to win over is also growing. While no one can predict exactly how many Latinos will turn out to vote and who they will support—Latinos, after all, are not a monolithic entity—Barreto estimates that they will make up about 10.4 percent of 2016 voters, a slight increase from previous years.

Latino voters have tended to vote for Democratic presidential candidates. That trend is likely to continue. But as the Latino share of the vote increases, Barreto noted, there are less non-Latino votes to win, meaning Republicans will need to pick up support from Latinos.

He estimates that Republicans will pick up about the same share of white voters as in 2012—just shy of 60 percent. But that could change, too. Voter turnout among young people increases during presidential elections and "the young people who are coming into the electorate today ... are not nearly as conservative as the older, silent generation who have been exiting," he said.

It's not just national figures that matter. The number of Latino voters who turn out in individual states will be critical, and the number of Latino voters is growing in swing states like Colorado. Barreto calculates that the Republican candidate would need 44 percent of Latino voters to cast GOP ballots in Colorado, and 47 percent in Florida. Ohio and Virginia also have large and growing Latino populations, Barreto said, meaning Latino voters could be decisive in those states.

"Republicans do seem to have quite a mountain to climb," said Frank Sharry, executive director of America's Voice, a group that advocates on behalf of immigration reform and requested the Latino Decisions analysis.

While Democratic front-runner Hillary Clinton has been "leaning in" on issues that Latino voters tend to care about, such as immigration reform, Sharry said, Republican candidates have been slower to lend their support

Latino Decisions has developed an interactive "threshold calculator" that anyone can use to make their own predictions. "The bottom line is that the Republican Party has a brand problem with Latinos," Sharry said.

"The bottom line is that the Republican Party has a brand problem with Latinos."—Frank Sharry, America's Voice

Yet he cautioned that Democrats do not have a lock on Latino voters either. His group and others will have to run voter mobilization campaigns, he said, to encourage people to turn out. If they do, however, Republicans will have an uphill battle when it comes to reclaiming the presidency.

This article is from the archive of our partner National Journal.

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