Barack Obama secured enough delegates to win the Democratic nomination on Tuesday, passing the threshold of 2,118 needed to become the party’s candidate.

“Because you chose to listen not to your doubts or your fears but to your greatest hopes and highest aspirations, tonight we mark the end of one historic journey with the beginning of another — a journey that will bring a new and better day to America,” Obama said in his victory speech in St. Paul, Minn.

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But rival Hillary Clinton says she’s not dropping out yet.

“Given how far we’ve come, and this has been a long campaign, I will be making no decisions tonight,” Clinton told fans gathered in New York City. She said she would make a decision in the “best interest” of the party and the nation in the coming days about how to proceed, after consulting with her supporters.

But Obama was ready to claim the nomination, and used his address to express his hope for the future, which included changing the country’s direction in environmental policy: “If we are willing to work for it, and fight for it, and believe in it, then I am absolutely certain that generations from now, we will be able to look back and tell our children that this was the moment when we began to provide care for the sick and good jobs to the jobless; this was the moment when the rise of the oceans began to slow and our planet began to heal; this was the moment when we ended a war and secured our nation and restored our image as the last, best hope on Earth.”

Not to let Obama steal the show entirely, John McCain also gave a speech tonight in New Orleans, in which he painted himself as “the right change” and Obama as “the wrong change.” He talked up his energy policy as one of the ways he’d bring about that change: “No problem is greater than America’s dependence on foreign oil,” said McCain. The next president “must be willing to break with previous administrations … and put us on a course to energy independence,” he said, proceeding to criticize Obama’s record on energy.

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But Obama also had fighting words for John McCain on energy: “Maybe if he went to Pennsylvania and met the man who lost his job but can’t even afford the gas to drive around and look for a new one, he’d understand that we can’t afford four more years of our addiction to oil from dictators.”

Obama continued: “That man needs us to pass an energy policy that works with automakers to raise fuel standards, and makes corporations pay for their pollution, and oil companies invest their record profits in a clean energy future –- an energy policy that will create millions of new jobs that pay well and can’t be outsourced. That’s the change we need.”

Find out more about Obama’s environmental stances by checking out Grist’s interview with the candidate and fact sheet on his platform and record.