Congress reconvened amid a new world order Monday, opening a lame-duck session shadowed by Donald Trump’s election, with perilous new opportunities and risks confronting the GOP.

House Speaker Paul Ryan began the day affirming that the Republican congressional majority is strongly aligned with the new president-elect, whom Ryan had initially refused to endorse and some congressional Republicans never backed.

Ryan enjoined colleagues to “hit the ground running as we join forces with the new Trump administration.”

“We need to seize this moment, and come together like never before,” the Wisconsin Republican wrote in a letter to the House GOP. “We cannot be timid about this: the country has voted for change, and we must deliver.”

In his letter, Ryan sought support for another term as speaker a year after first assuming the job. Closed-door House GOP leadership elections will take place on Tuesday, and Ryan is expected to prevail despite some rumblings of discontent among conservatives.

He would then need to be elected on the floor of the House by the full complement of Republicans and Democrats once the new Congress convenes in January. Republicans will control both chambers of Congress and the White House, giving the GOP a monopoly over Washington for the first time in more than a decade.