With Democrats now poised to take control of the US Senate, the prospects for president-elect Joe Biden to pursue his aggressive policies to address climate change and other major environmental problems has expanded significantly.

n light of recent events in Washington – including the storming of the US Capitol by supporters of outgoing president Donald Trump – the sea-change in favor of the democrats following Georgia’s runoff election has been somewhat lost in the fray. But the new composition of the Senate under the incoming administration, as well as a Democratic majority in the House of Representatives, will give Biden a majority as he seeks to enact his pledge of net zero emissions by midcentury.

Democratic control of congress will also make it easier for Biden to reverse a host of environmental rollbacks enacted by the Trump administration as well as win confirmation for pollical appointees throughout the government who can shift policy toward a cleaner future. With Biden’s party commanding the legislative and executive branch, it will likewise be easier to press for much more generous federal support for renewable energy, environmentally friendly infrastructure, expanded tax breaks for electric vehicles and stricter energy-efficiency standards.

Still, the majority is razor-thin, and major environmental legislation could demand compromise with Republicans and some of the Democratic party’s more conservative members. The Georgia senatorial victories last week split the Senate down the middle – 50 Democrats and 50 Republicans, with the tie-breaking vote in the hands of Kamala Harris, Joe Biden’s vice president, who will oversee the chamber. Democrats also lost 14 seats in the House of Representatives, narrowing their hold to 222 seats to 212.

Far reaching climate action could also be stymied by a deeply conservative Supreme Court as environmental initiatives are sure to be challenged by Republican attorneys general from conservative states.

The administration will also feel pressure from activists, who say they are organizing a sweeping network to mobilize around climate justice and climate change designed to hold Biden’s team to its bold environmental promises.

“The change in Senate leadership and committee leadership will place climate change and clean energy legislation and oversight much higher on the agenda,” Scott Segal, a lobbyist at the law firm Bracewell, which represents an array of energy-related companies, told the Washington Post. But he added, “Given the narrow margin of leadership in both the House and Senate, there still isn’t much in the way of open-field running for comprehensive climate change legislation.”

The former vice president’s climate action pledge includes an ambitious $2 trillion economic plan that would accelerate a clean-energy transition, cut carbon emissions from the electricity sector by 2035 and achieve net-zero emissions by 2050.

This climate plan are in line with targets set by other major economies including China and the European Union. However, many of the policies would have been blocked by a Republican-controlled Senate. The $2 trillion plan will still be a tough sell even as Democrats take over, but experts are optimistic for some broader bipartisan-backed climate legislation to pass in upcoming years.

“Democratic control of the Senate means funding for climate action and the energy transition through appropriations, policy advances through the reconciliation process, political support and messaging from Congressional leadership, and potentially, if one is being highly optimistic, big ticket climate legislation with some level of bipartisan support,” Michael Burger, head of the Sabin Center for Climate Change Law at Columbia University, told CNBC news.

Bipartisan climate legislation could address policies that target wind and solar energy, carbon capture and tax incentives for clean energy, among other things.

“For years people have been talking about Republicans in the Senate who favor climate action waiting for the opportunity to make a jailbreak from the party’s anti-climate, anti-environmental agenda,” Burger said. “Here’s the time to make the break.”

Some environmental experts worry that not enough Democrats will take serious climate action and expect more modest bipartisan legislation that won’t match demands of climate advocates or actions by other countries.

Biden said in a statement last week that he’s determined to work with Republicans on federal, state and local levels to battle the coronavirus pandemic and other crises.

“Georgia’s voters delivered a resounding message yesterday: they want action on the crises we face and they want it right now. On covid-19, on economic relief, on climate, on racial justice, on voting rights and so much more,” Biden said. “They want us to move, but move together.”

Once Biden is sworn in on Jan. 20, he has pledged to immediately bring the US back into the Paris Climate Agreement, the global pact forged five years ago among nearly 200 nations to set climate targets in order to avoid the worst of climate change. Trump formally withdrew the US from the agreement in November.

The Biden administration is also set to reverse many of Trump’s 84 completed environmental rollbacks and rescind a great deal of the president’s executive orders on energy.Additionally, one of Biden’s earliest expected executive orders would require that every government agency and department tackle climate change.

“The climate crisis is not coming. It is here now,” Michelle Deatrick, founder of the DNC Environment and Climate Crisis Council, said in a statement.

“President-elect Biden and the administration he is building understand this and are ready to act,” Deatrick said. “And now, thanks to the amazing work of so many on the ground in Georgia, the path to sensible and needed solutions to this crisis just got a lot easier.”