A number of climate activists who rallied on Sunday in New York City for the largest climate change march to date, said they aren't convinced Hillary ClintonHillary Rodham ClintonWhat the 2016 election can tell us about 2018 midterms Wis. Dem demands apology for Republican's 'communist' jab Ellison as DNC chair will cement Democrats’ position in the minority MORE is their candidate if she runs for president.
Founder of the prominent activist group 350.org, Bill McKibben, told MSNBC that the former secretary of State has a lot to prove.
“I think Hillary Clinton has an awful lot to demonstrate to environmentalists and people who care about climate change,” said McKibben, whose group helped organize Sunday's march.
“She oversaw the complete fiasco that was the Copenhagen Conference as secretary of State. That was the biggest foreign policy failure since Munich. It’s not a proud record," he added.
In a recent renewable energy speech in Las Vegas, however, a majority of Clinton's speech was dedicated to sounding the alarm on climate change.
In her book, "Hard Choices," the likely democratic front-runner in 2016, made the 2009 Copenhagen meeting the focus of one of the chapters, touting her work with President Obama to get critical conversations flowing between the U.S. and China.
Still, actor Mark Ruffalo isn't sure Clinton will get support from greens, a critical faction of the base that has helped Obama.
Clinton's problem is her stance on fracking for natural gas, a significant element of the U.S. energy boom, which Obama supports as well.
"Unless she changes that, the climate change voters, the people who take this very seriously, are not going to be able to get behind her,” Ruffalo told MSNBC.
“If someone can offer up another way forward, [climate voters] are going to get behind that person. Just like Obama, they got behind him,” Ruffalo added, suggesting Sens. Elizabeth WarrenElizabeth WarrenOvernight Healthcare: Medical cures bill finally heads to White House Senate sends far-ranging medical cures bill to Obama's desk Sanders: GOP blocked 'Trump proposal' to lower drug prices MORE (D-Mass.) or Bernie SandersBernie SandersOvernight Healthcare: Medical cures bill finally heads to White House Overnight Regulation: Obama's reg czar under pressure | Fight looms over Trump EPA pick Overnight Energy: Trump taps EPA foe to head agency | Energy reform bill officially dead MORE (I-Vt.) as possible alternatives, according to MSNBC.
“These are people who get this, who are not beholden to this 100-year-old fossil fuel stranglehold on leaders like Hillary Clinton," Ruffalo said.