WASHINGTON - With relatively little separating Barack Obama and Hillary Clinton on the major issues, the two Democratic presidential candidates are earning a nearly equal number of votes nationwide by attracting starkly different demographic groups, a trend that could determine who wins the nomination.
Clinton's supporters tend to be white women, lower-income, and Hispanic voters, according to Super Tuesday exit polls. Obama is popular among African-American, male, higher-income, and younger voters.
To be sure, many voters do not necessarily make their decision in the ballot booth based on race, gender, ethnicity, or similar factors. But political analysts who pored over exit polling data said demographics are influencing a historic contest that will end with Democrats choosing the first woman or the first African-American nominee for president.
"Each of them [has] a fairly distinct demographic coalition," said pollster Mark Mellman, a Democrat not affiliated with either campaign. "His coalition is AfricanAmericans, upscale, and younger [voters]. Her coalition is more downscale and Latinos. In different states, different coalitions will [provide an] advantage."
Exit polls conducted on Super Tuesday, when more than 23 million voters in 24 states cast ballots, underscore the differences.
Black voters chose Obama over Clinton 82 percent to 16 percent in the Super Tuesday states, while whites supported Clinton 52 percent to 43 percent over Obama. Hispanics preferred Clinton to Obama 61 percent to 37 percent.
Obama has gained on Clinton by gradually increasing his appeal among whites and younger voters, according to Peter Ubertaccio, professor of political science at Stonehill College in Easton, Mass.
"He is trending upward into the demographic areas where he needs to improve," Ubertaccio said. "The question is whether, with the compressed primary schedule, it is too late" to collect enough delegates to surpass Clinton and win the nomination.
Obama, in a Chicago news conference yesterday, acknowledged he must widen his appeal to demographic groups besides African-Americans.
"As Latino voters get to know me, we do better," Obama said. "And so it's just a matter of us getting more information to them."
Asked about Clinton's advantage among blue-collar voters in some areas, Obama said he will try to ensure such voters know more about him in the coming weeks.
Clinton strategist Mark Penn, meanwhile, said yesterday that the senator has a "diverse constituency across many ethnic groups" and that Latinos "gave us very strong support. This is perhaps the most significant, the fastest-growing voter community in America."
Both the Obama and Clinton campaigns see advantages in the demographic makeup of voters in upcoming contests.
For example, the Obama campaign expects he will do well in next week's primaries in Maryland and Virginia, which have large African-American and upscale populations. Obama won the Georgia primary, which has a 29 percent black population, similar to Maryland's 28 percent.
The closer contest may be in Virginia, a Southern state whose African-American population, 20 percent, is closer to the 17 percent black population in Tennessee, which Clinton won by a substantial margin on Super Tuesday.
By contrast, the Clinton campaign expects the March 4 contest in Texas, where the population is 36 percent Hispanic and 12 percent black, to favor the New York senator. The Texas demographics are similar to those of California, which has a 36 percent Hispanic and 7 percent black population and which Clinton won handily.
Other key states, however, may not have large enough minority populations to tilt the outcome toward either candidate.
Ohio, which holds a potentially crucial March 4 contest with a large number of delegates at stake, is 12 percent black and 2 percent Hispanic. Pennsylvania, whose April 22 primary also could be decisive, is 11 percent black and 4 percent Hispanic. Democrats in those two state tend heavily to be working class, a factor that could help Clinton, according to Mellman, the Democratic pollster.
The age of voters is another key demographic.
Consider the results in Missouri, where race, gender, and ethnicity did not appear to be decisive factors. The two candidates drew nearly equal numbers of men and women, and the state has a modest minority population. The difference was the turnout among younger voters, who voted in greater numbers for Obama, handing him a narrow victory.
Ubertaccio, the Stonehill professor, said Obama needs a similarly large and overwhelmingly supportive turnout by younger voters in coming primaries.
Obama is trying to increase his appeal to Hispanics. Clinton is trying to win back support among African-Americans, hoping to erase the perception that she and her husband, Bill, injected racial issues into the campaign.