The same study found that 2.1 percent of this year's GOP delegates are black. Republican activists see themselves as defenders of hard work and merit without regard to creed or color - their presidential nominee, after all, is a Mormon - and they recoil at Democrats' use of an affirmative-action system to pick some delegates based on race, ethnicity, and sexual orientation.
The disparities are evident to any observer of both conventions. Though Jewish Republicans handed out "Oy vey Obama" buttons in Tampa, the GOP convention placed much less emphasis on demographics than was already on display here Monday, at a festival downtown to mark the eve of the Democratic convention that officially begins Tuesday.
The thousands who attended the festival included gays, mixed-race families, and many African Americans. A succession of black women took photos in front of an oversize picture of President Obama plastered on a truck sponsored by the National Jewish Democratic Council. Dozens lined up to spin a wheel for free regalia from the Human Rights Campaign, a gay-rights organization. Buttons proclaimed groups such as "Native Americans for Obama."
For the first time, this year marriage equality is in the Democratic platform. That means Steven Goldstein, the gay-rights leader in New Jersey and a delegate, can speak of feeling "completely comfortable" at a Democratic convention.
"We don't feel tolerated; we feel embraced and loved," he said Monday.
Similarly, Barbra "Babs" Casbar Siperstein of Edison, N.J., a transgender delegate and the first transgender member of the Democratic National Committee, said she was heartened by a 2009 change in party bylaws that strengthens language on bias against transgender people.
Siperstein, one of 12 transgender delegates nationally, said she voted for Republicans in the past. She now finds it hypocritical that "they talk about small government, but they basically have big government in your bedroom."
Though the talk of inclusion is heralded as gospel by Democrats, Republican delegate Sherine El-Abd doesn't buy it. An Egyptian American from Clifton, N.J., who is a Muslim, she said she initially became a Democrat - but "I left them because of their lack of inclusion."
She added: "They are just full of rhetoric. And I need to see more than talk. Talk is cheap."
El-Abd, who was in Tampa last week, said she wearies of Democrats who pander to her community with Arabic phrases such as salaam alaikum ("peace be unto you") as if "we're supposed to melt."
"They come to our events, they eat our food, they tell us how wonderful we are - and I find it patronizing and offensive," she said in a telephone interview. "Whereas I don't feel the patronizing from the Republican Party. I am treated like an equal. Because that's what I am."
While the GOP values "loyalty and hard work," she said, Democrats value polls, give some groups "a lot of lip service," and use "quotas" to pick delegates.
The Democratic Party does have what it calls an "affirmative-action program" to attract delegates of underrepresented racial and ethnic groups, while a less stringent "inclusion program" brings in youth, gays, and the disabled.
That helps explain why New Jersey's 172 voting delegates include 47 blacks, 33 Hispanics, 16 Asian Americans, and two Native Americans. Ten delegates are disabled; 16 identify as LGBT.
The delegation is actually more diverse than New Jersey, party officials said.
And though Democrats nationally choose about twice as many delegates as Republicans, consider this: There are more blacks in the Democrats' Pennsylvania delegation than the total of black GOP delegates at Tampa.
On TV, such visuals can make the Democratic Party appear as though it is the home for nonwhites.
Jim Burn, chairman of Pennsylvania's Democrats, said that in recruiting delegates, "it was critically important that we reflected the diversity of the commonwealth itself."
Burn said the GOP convention "was like watching Ozzie and Harriet for three days."
Republicans would strenuously reject that characterization. Nonwhite speakers starred in Tampa: former Secretary of State Condoleezza Rice, an African American; Sen. Marco Rubio of Florida, a Cuban American; Mia Love, a congressional candidate from Utah who is Haitian American; New Mexico Gov. Susana Martinez, a Latina.
Even so, Republicans face an increasing inability to secure votes from racial minorities, one expert contended.
"Having a party system based on race is not that different from the party systems in the Middle East based on religion," said analyst David A. Bositis, who compiled racial data on the delegates for the nonpartisan Joint Center for Political and Economic Studies in Washington.
A "chasm" now exists between Republicans and African Americans, Bositis said. Part of it is a response to the rise of the tea party, he said, which is perceived as hostile to blacks. He said only two of the 165 national GOP committee people are black.
Although Obama helped bring additional blacks into the Democratic column, Bositis said a bigger draw is some of the party's policies. He said that Obama's health-care reform law, for example, helps minorities more than whites because they are more likely to be uninsured.
People at Monday's festival here gave varied reasons for being drawn to the Democrats.
Robert Thompson of Oklahoma, an American Indian from the Muscogee Creek Nation, said he was selected as a delegate due to the party's affirmative-action system.
"Obama's policies are going to be a lot more helpful to people of color and poor people," Thompson said. He cited an Obama restoration of cuts to health care for tribes.
Washington state delegate Liz Campbell, who is white, went to the African American caucus meeting for the Democrats on Monday. "Democrats are the party of 'we,' " she said. "They're the party that cares about people who don't have a voice."
Or, in Republican El-Abt's views, a party that wants to look that way.
"The Democrats use this as a PR thing, the diversity," the GOP delegate said. "They invest in it so they get more votes in that way."
Contact Matt Katz at 609-217-8355, email@example.com, or follow on Twitter @mattkatz00. Read his blog, "Christie Chronicles," at www.philly.com/ChristieChronicles.
Inquirer staff writer Thomas Fitzgerald contributed to this article.