If we ignore global warming much longer, we'll face a world of perpetual disaster, so there's no larger question for presidential candidates than who is more likely to tackle it successfully. Although Obama's and Clinton's positions are similar, he seems far more likely to. The key difference is their ability to mobilize a grassroots base to demand that the necessary changes get passed.

If you look only at the candidate platforms, both Obama's and Clinton's are excellent. John Edwards was the first to come up with a comprehensive plan, but Obama soon did too, followed by Clinton. Both Obama and Clinton focus on renewable energy in their speeches and ads, pledging major incentives and R&D programs for renewables, increased portfolio standards for utilities, and  cap-and-trade systems with decreasing limits where permits would be auctioned off, not just given away. Both support green jobs programs to benefit communities. Both talk of continuing to tighten efficiency standards for buildings, vehicles, and businesses. I wish both took firmer stands against nuclear power and liquid coal, but either would offer a strong alternative to our current inaction. Their programs are also both considerably better than that those John McCain suggests. While McCain talks a decent line, especially compared to his numerous climate change-denying Republican colleagues, he equivocates far more on the critical details, supports considerably more modest carbon reduction standards, and this past December abdicated the chance to cast the critical cloture vote and end a Republican filibuster that blocked the recent energy bill's most important provisions. Both Obama and Clinton get the urgency of the issue as much as any mainline American politician who isn't named Al Gore.

But I think Obama is far more likely to pass anything close to the legislation we need, because of his ability to mobilize ordinary citizens. Clinton emphasizes her insider knowledge, her familiarity with process. But in a period when Republicans first prevented Democratic bills from coming to the floor, and then filibustered them if they did, she's mostly been unable to coalesce participants across the admittedly entrenched political divides, unless you count crossing the aisle to support a flag-burning bill or backing the Iraq war. Her track record's no worse than other Democratic Senators, and she did successfully co-sponsor bi-partisan legislation to protect bonuses for wounded veterans and extend family medical leave for wounded soldiers, while introducing a still-in-process bill to improve mental health services for seniors. But it's a record certainly matched by Obama. In his four-year-briefer tenure, he's secured major Republican support to pass a major transparency bill that publicly lists all organizations receiving Federal funds, how much they've received, and the purpose of their grant or contract. He's passed another that provides resources to seek out and destroy surplus and unguarded stocks of conventional arms—like land mines and shoulder fired missiles--in Asia, Europe, Latin America, Africa and the Middle East. And together with Russ Feingold, he played a key role in developing and passing a law that eliminated gifts of travel on corporate jets from lobbyists to members of Congress and required disclosure of bundled campaign contributions. Even if you ignore his major achievements in the Illinois legislature--like bringing police chiefs and civil liberties advocates together to craft and support a bill providing clear monitoring of police interrogations, and passing a bill extending health care to 150,000 state residents--I'd say evidence of insider ability is a wash.

The critical difference between Obama and Clinton is their potential to encourage ordinary citizens to speak out on the changes that we need. And that will be essential. If you strip away the racial connotations, that's actually the core of the debate over Clinton's claim that LBJ was more critical to the passage of the Civil Rights Act than Martin Luther King. For all that I loathe Johnson's escalation of the Vietnam War, he did stake his entire political capital and massive skill to navigate the Civil Rights and Voting Rights Acts through Congress--even though he knew it would lose the Democrats the South for a long time to come.  But without the massive citizen movement that put civil rights onto the nation's conscience and at the top of its political agenda, he'd never have taken these stands. When you read books like Taylor Branch's wonderful history of America in the King years, it's clear how much both LBJ and Kennedy viewed the civil rights movement as a politically loaded intrusion on their other agendas. Kennedy did all he could to pressure King and other civil rights leaders not to hold the 1963 March on Washington. But as the pressure kept building, they finally answered the movement's call and lent their moral support to it, just as Franklin Roosevelt played a critical role by lending his support to America's resurgent union movement. We'll need a similarly powerful massive movement now--and ideally a president willing to nurture it--to overcome the massive dollars and entrenched political clout of companies like Exxon/Mobil, Peabody Coal, and General Motors.  

In that context, there's no comparison between the candidates. Obama evokes the power of citizen movements in every speech he gives. He explicitly challenges ordinary citizens to see themselves as part of a lineage of change, with their own political participation following in the footsteps of America's most fundamental movements for justice. Obama evokes those roots when he talks of slaves and abolitionists who "blazed a trail toward freedom through the darkest of nights," and of "workers who organized; women who reached for the ballot…and a King who took us to the mountaintop and pointed the way to the Promised Land."

Obama explicitly calls for citizens to act beyond the confines of electing him to office. His campaign echoes this call by relying on volunteers to organize themselves, take their own initiative, and find common strength in connecting with each other. The campaign provides materials, talking points, and video images, and is extraordinarily organized in ensuring that every critical precinct gets walked and every key household gets called. They learned the rules of the Texas caucus and Pennsylvania delegate systems, for instance, while the Clinton camp was reduced in the case of Texas to complaining and threatening lawsuits and failed to file a full slate of Pennsylvania delegates. Yet Obama's campaign has also sacrificed a significant amount of control over precisely how their volunteers reach out once they're engaged. In my home state of Washington, operations were run for months by an entirely volunteer group that included several former Bush and Ross Perot supporters in key roles who'd been disillusioned by disasters like Iraq, and then inspired by Obama's words. Their Ohio volunteer phone script, for instance, offers a standard summary of issues to raise, but also explicitly encourages volunteers to talk about their specific reasons for participating. The campaign has also continually helped connect ordinary citizens with each other, consistent with Obama's years as a community organizer and then as a lawyer representing these same grassroots organizations. Because these new connections are created in a way that's likely to last past the election, they'll make these new participants part of an independent base for change that can both help Obama pass key legislation on issues like climate change, and press him to act more strongly when he compromises unduly.

Clinton's campaign, by contrast, has been top-down and controlled from the start, giving local campaigners far less latitude.  Initially, she was praised for keeping everyone on message and on a short leash. As her seemingly inevitable lead began to shrink, she's switched to attacking Obama's rhetoric and experience, dismissing his waves of new supporters, and in her most recent ad, evoking Cheney-style fear tactics about who will be in the White House when the phone rings at 3 AM. As an entrenched symbol of loathing to the political right (in a recent Mike Huckabee speech, his lines attacking Hillary got more applause than anything else he said), and whom down-ticket Democrats are terrified of seeing head the ticket in conservative states, she's unlikely to build the overwhelming majority we need to help shift our economy's entire energy base.

I'd love to see America's climate change politics approach Europe's, where conservatives like East Germany's Angela Merkel have taken the lead on many efforts and even Nicolas Sarkozy just posed proudly with Al Gore after passing a major French climate initiative. When I met the environmental minister from the conservative party that runs Denmark, she described taking visiting Republican Senators together with climate scientists to see the melting Greenland ice caps. "You're a conservative. I'm a conservative," she said. "I don't understand why the US isn't participating and leading on this issue."  But we haven't. We couldn't get even a handful of Senate votes for the Kyoto Treaty. American oil and coal companies like Exxon/Mobil and Peabody have spearheaded the international funding of climate change deniers. Our level of popular denial remains greater than citizens of countries like France, Great Britain, and even Brazil and China, with the latter also passing more stringent automobile fuel standards.  We're making major local progress: More than 700 cities have signed the US Mayors Climate Projection Agreement. But we will only achieve the necessary national change if we get enough citizens involved to radically shift our culture and politics.

This will take independent efforts like the 1Sky Coalition, the nation-widel StepItUp rallies that preceded it, and the campus organizing that  produced the 6,000-student PowerShift conference last November. Whoever wins, we'll need to mobilize more, not less, to see the changes we need. But on an issue this overwhelming and potentially terrifying, we'll need leaders who can help inspire people to take the leap of faith of acting whether or not they know their actions will succeed. Because as Jim Wallis of the religious social justice magazine Sojourners has said, "Hope is believing in spite of the evidence, and then watching the evidence change."

If I look at both Obama's record and his campaign, I see someone who understands the critical role of citizen movements and works to build them as a force capable of creating major change. That's what we've needed to address the major challenges of the past. It's what we'll need to address this ultimate crisis we've created through the combination of technological inventiveness and short-focus blindness. The Clintons may have spoken out against the Vietnam War when they were young, but they've been hedging their bets and distancing themselves from citizen movements ever since. We need a movement-building approach for global climate change—and for all the other crises America's next president will inherit from Bush's disastrous reign.

Paul Rogat Loeb is the author of The Impossible Will Take a Little While: A Citizen's Guide to Hope in a Time of Fear, named the #3 political book of 2004 by the History Channel and the American Book Association. His previous books include Soul of a Citizen: Living With Conviction in a Cynical Time. See   To receive his articles directly email with the subject line: subscribe paulloeb-articles