With just five candidates at Tuesday's Democratic primary debate, the stage almost looked empty compared with the Republican debates. The most recent round of GOP contests featured a total of 15 candidates sparring in two separate events, including an 11-person primetime showdown.
Many people surely expected the Democratic candidates to show plenty of disagreement with Republicans on how to address the nation's most pressing issues. But we saw the Democratic candidates on Tuesday hit a number of topics that barely registered in the Republican debates, if at all.
While the first two GOP debates touched on topics that included cutting taxes, restricting abortion access, illegal immigration, vaccine skepticism and Secret Service aliases -- all issues, with the exception of the last, that debate moderators likely thought were at least somewhat important to GOP primary voters -- the Democratic candidates discussed topics that highlighted key differences between the parties.
The Democratic candidates mentioned racial divides in their introductions, noting disparity in income, education and economic opportunity, and incarceration rates. But the real power came when the candidates were asked flatly, "Do black lives matter, or do all lives matter?" Most of the Democrats responded with resounding support for the Black Lives Matter movement. Former Virginia Sen. Jim Webb built on previous comments about "white culture" and discrimination against white people, choosing to go with a statement that "all lives matter."
The GOP contenders, however, have failed to utter the word "black" even once during either of their debates. Sen. Rand Paul (R-Ky.) was the only candidate to mention the words "African-American," during a response to a question about marijuana arrests.
2. Campaign finance reform and Citizens United
Sen. Bernie Sanders (I-Vt.) came out firing on this issue, blaming the Supreme Court's "disastrous" Citizens United decision for a campaign finance system that is "corrupt" and "undermining American democracy."
He later touted that he is not raising money from a super PAC, the sort of independent political action committee that allows for unlimited amounts of money, including from corporations and unions, to fund campaign efforts in a variety of ways. Webb made the same point, highlighting the grassroots nature of his campaign.
The only significant Republican mentions of campaign finance issues have come in the form of Donald Trump pointing out that super-wealthy people -- like him -- can effectively buy favors from politicians.
3. Domestic surveillance
Democrats fielded a question about whether Edward Snowden was a hero or a traitor for leaking classified documents revealing the National Security Agency's mass surveillance program. Former Rhode Island Gov. Lincoln Chafee was the only candidate to suggest Snowden shouldn't be charged for his whistleblowing. "I would bring him home," Chafee said. "The American government was acting illegally."
During a broader discussion about the Patriot Act, Chafee also railed against the warrantless surveillance of Americans. Sanders suggested he didn't regret his vote against the legislation and would scale back larger NSA surveillance programs. Former Secretary of State Hillary Clinton defended her vote for the Patriot Act, calling the law necessary "to put in place the security that we needed."
The issue of surveillance came up only briefly at the first GOP presidential debate, when Paul and New Jersey Gov. Chris Christie used it to launch personal attacks on one another.
4. Wall Street reform
The Democratic candidates came out strongly in favor of additional regulation on big Wall Street banks. In his closing speech, for example, former Maryland Gov. Martin O'Malley vowed to "follow through on the promise to protect the Main Street economy from Wall Street, separate out the too-big-to-jail and too-big-to-fail banks." Sanders said that "Wall Street's greed and recklessness wrecked this economy."
The GOP debates included only one mention of big banks on Wall Street, and it concerned Wall Street's influence on Washington rather than on the economy. Republicans did mention The Wall Street Journal, however.
5. "The 1 percent"
Sanders took the lead on the issue of income inequality, repeatedly borrowing a line from his stump speech about exactly how much of the wealth is controlled by the richest Americans.
"And what democratic socialism is about is saying that it is immoral and wrong that the top one-tenth of 1 percent in this country own almost 90 percent -- almost -- own almost as much wealth as the bottom 90 percent," said Sanders in his introduction. "That it is wrong, today, in a rigged economy, that 57 percent of all new income is going to the top 1 percent."
Candidates also repeatedly name-checked the middle class during broader economic discussions. In the GOP presidential debates, candidates only mentioned the words "middle class" four times during policy discussions.
6. College affordability
The Democratic candidates agree: The price of college is too damn high. Both Clinton and Sanders criticized the exorbitant costs and called for broader reforms to lower the burden of student loan debt and to make higher learning less expensive. O'Malley joined in, saying politicians needed to take bold action to "make college a debt-free option for all families instead of saddling our kids with lifetime crushing debt."
College affordability hasn't come up at Republican debates. In fact, most mentions of college have come when the GOP candidates describe their own educations.
Republican candidates certainly have some ideas on foreign policy, but diplomacy has not exactly been one of them. In fact, the word "diplomacy" has only been uttered one time over two GOP presidential debates.
During a discussion about how to handle Russian intervention in Syria on Tuesday, Clinton took the opportunity to demonstrate her experience.
"You know, diplomacy is not about getting to the perfect solution. It's about how you balance the risks," she said. "I think we have an opportunity here and I know that inside the administration this is being hotly debated to get that leverage to try to get the Russians to have to deal with everybody in the region and begin to move toward a political diplomatic solution in Syria."
8. Paid family leave, health care and insurance
These three issues have gone almost entirely ignored by Republicans. On Tuesday, Democrats made the contrast clear, calling out the U.S. for failing to provide some of the basic health services and workplace benefits that are guaranteed in industrialized countries around the world.
9. Benghazi and Clinton's emails
The Democratic candidates ended up spending time on a few issues that could have been taken out of the GOP playbook.
In the Republican debates, candidates have -- perhaps surprisingly -- made only brief mention of the Benghazi attack and Clinton's emails, two controversies that have plagued the former secretary of state. On Tuesday, however, questioning turned to those topics and led Democrats to come to an overwhelming conclusion: Benghazi is not the scandal Republicans want it to be, and people are sick of hearing about those "damn emails."
Clarification: This story has been updated to note that two Republican candidates did reference domestic surveillance in the context of attacking one another's records on national security and civil liberties.
For the latest updates on tonight's debate, visit our liveblog.
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