Left: Hillary Clinton campaigns in Ohio. Right: Bernie Sanders greets supporters in New Hampshire.Jeff Swensen, Kayana Szymczak/Getty Images

This article is from the archive of our partner National Journal

LAS VEGAS—As the Democratic presidential contenders gather here for their first debate tonight, the changing composition of the party’s electorate looms as the wild card in the unexpectedly competitive race.

Over recent years, women, racial minorities, college-educated Whites, and young people have all grown as a share of the Democratic primary voting base. The first two groups have largely favored Hillary Clinton in early polling, while the latter two have frequently bolstered Sen. Bernie Sanders, Clinton's principal rival.

Amid these shifting currents, Clinton’s commanding position among the primary electorate’s growing number of non-White voters is the reason most Democratic strategists still consider her the prohibitive favorite in the race.

That’s despite Sanders’s early support in the kick-off contests of Iowa and New Hampshire, two virtually all-White states with large numbers of the college-educated liberals expected to provide his core support. “White college-educated people are his groove,” says longtime Democratic pollster Mark Mellman. “But until, and unless, he can make that crossover into minorities, it’s very hard for him to get the nomination as a practical matter.”

Clinton’s demographic advantages, though, underscore the potential of Vice President Joe Biden to disrupt the race if he enters it. Most strategists believe Biden would be strongest among constituencies that now mostly bolster Clinton: blue-collar and older Whites, African-Americans, and maybe Latinos. If Biden entered and drew disproportionately from those groups, without attracting as much support from the white-collar Whites that Sanders is likely to rely on, Clinton’s edge over the field wouldn’t entirely evaporate. But it could quickly become more precarious.

Clinton relied on an admirably consistent coalition through her marathon struggle against President Obama during the 2008 primaries. According to a cumulative analysis by ABC pollster Gary Langer of all 39 exit polls conducted during the 2008 race, Clinton carried just over three-fifths of both noncollege Whites and Latinos. She also won 54 percent of college-educated White women, improving her performance among them as the primaries progressed. Obama countered by amassing over four-fifths of all African-American voters and carrying a 55 percent majority of college-educated White men.

Looking across all the states, Clinton also won about three-fifths of seniors (while Obama also won about three-fifths of young people). While she carried 51 percent of voters earning less than $50,000, Obama won an equal 51 percent of those earning over $100,000. (Voters earning between $50,000 and $100,000 split exactly in half between Clinton and Obama.)

According to Langer’s analysis, college-educated Whites, Whites without a college degree, and non-White voters each cast almost exactly one-third of the total Democratic primary vote in 2008. That continued a long-term shift in the Democratic coalition away from the blue-collar and older Whites who provided its foundation from the 1930s through the 1960s and toward the alignment that the party relies on today: young people, minorities, and college-educated, unmarried and secular Whites, particularly women.

For the 2016 primaries, the key questions facing Clinton are whether she can hold her 2008 support, whether she can reach beyond it, and whether the groups that favored or resisted her are most likely to increase their share of the overall vote.

While Clinton won all Whites by a solid 55-to-39 percent margin over Obama in 2008, a succession of recent state polls have found Sanders gaining on her with those voters now. In just the past few weeks, Sanders has led Clinton among Whites in surveys released in New Hampshire (NBC/Marist and CNN/WMUR) and South Carolina (CNN/ORC); the two ran to a dead heat among Whites in a Field Poll of California voters released last week, and she led him among Whites by just a 33-to-30 percent margin in Virginia in a Christopher Newport University poll released Monday. The most recent Quinnipiac University Poll in Florida showed her leading among Whites but with just 37 percent. Clinton led more comfortably among Whites in the latest NBC/Marist Poll in Iowa and in the CNN/ORC survey released Monday in Nevada. National polls have generally still found her leading among Whites, though the most recent NBC/Wall Street Journal national survey gave Sanders a double-digit advantage.

With his passionate liberal stances, Sanders built his initial support mostly among white-collar White voters. But some of these recent polls—including the Marist survey in New Hampshire and the Christopher Newport University poll in Virginia—have also shown him leading among Whites without a college degree, a core constituency for Clinton in 2008. That may reflect polling variation—most primary surveys involve small samples subject to fluctuation—but it could also be an early indication that Sanders’s unflinching populist message is finding an audience with the remaining blue-collar component of the Democratic electorate.

The best news for Clinton is that polls generally show her holding support among Latinos and running up preponderant numbers among African-American voters, who gave Obama huge margins eight years ago. In the Virginia poll released Monday, she led Sanders among African-Americans by nearly five-to-one, even with Biden in the race, according to figures provided by Quentin Kidd, director of the University’s Wason Center for Public Policy.

The Quinnipiac Florida poll showed her leading among non-White voters there by four-to-one over Sanders and more than two-to-one over Biden. In the CNN/ORC poll of South Carolina released Monday, Clinton led Sanders among African-Americans by 15-to-one, even with Biden in the race. Without Biden, she attracted more than four-fifths of African-Americans in the state, the survey found. Similarly, without Biden in the race, the national NBC/WSJ poll found her attracting more than three-fourths of non-White voters against Sanders.

Sanders’s supporters believe he can improve those numbers as he becomes better-known among African-Americans and Latinos, but many Democratic operatives in the Obama orbit are dubious. “I just don’t ever see [Sanders] being the champion of poor brown and Black people,” said Bill Burton, Obama’s campaign press secretary in 2008 and later deputy press secretary in the White House. “African-Americans and Hispanics and noncollege Whites don’t really have the luxury of supporting some socialist from Vermont who seems like a good idea. These are people whose lives are hard, [they] are looking for someone who has a record of being a champion for them, not just in theory but reality.”

Unless Sanders can deepen his reach with ethnic-minority voters, he will find it difficult to win primaries beyond the relatively small list of states where Whites, especially those with advanced education, dominate the Democratic primaries—such as Connecticut, Oregon, Massachusetts, and Vermont. “The farther you get away from states where you can do well by rounding up a lot of college-educated White liberals and independents, I think he’s going to do worse,” says Ruy Teixeira, a senior fellow at the Center for American Progress and a leading Democratic analyst of demography and politics.

The last influential factor in all this is how the relative voting power evolves among the key groups in the Democratic primary electorate.

Since 2008, voters of color have increased as a share of the national eligible voter population by a substantial four percentage points, according to the nonpartisan States of Change project. Because they tend to identify mostly as Democrats, their numbers could rise even faster in the Democratic electorate—though that will depend on whether Clinton can turn them out as effectively as she and Obama did in a combined effort in 2008. Many analysts expect the share of college-educated Whites to also increase because their numbers in the overall population are growing, and Democrats are relying even more on their support than they did seven years ago.

Amid these gains, most Democratic number-crunchers expect blue-collar and older Whites to continue receding as a factor in the 2016 primaries, while remaining critically important in some key states like Ohio and Pennsylvania. That will challenge Clinton. “The net value of blue-collar Whites in the Democratic primary goes down in every passing year as it does in the country,” says Dan Pfeiffer, a former senior adviser to Obama.

Besides the hurdle of cracking Clinton’s support from voters of color, the most important challenge for Sanders may be turning out the young voters who buoyed Obama in 2008—and who are flocking to his rallies. That mirrors the test Clinton faces in motivating voters of color—and underscores that who votes may be as important as how they vote in determining the next Democratic presidential nominee.

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

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