Johnson received 220 votes with no Republicans voting against him.
Rep. Mike Johnson was elected as the 56th speaker of the House Wednesday after three failed GOP tries. Unlike in previous ballots, every single Republican voted for him, giving him 220 votes.
The hard-liner and 2020 election denier said the House will have an “aggressive schedule in the days and weeks ahead.”
The House has faced a chaotic speakership battle that has dragged on for three weeks.
Moments after Rep. Mike Johnson was elected speaker, a new sign with his name was installed outside the speaker's office in the Capitol.
The sign bearing former Speaker Kevin McCarthy's name was removed at some point Tuesday evening.
-ABC's Lauren Peller and Mariam Khan
Rep. Mike Johnson called it the "honor of a lifetime" to win the House speakership in a 220-209 vote after three weeks without a permanent speaker.
"Thank you to my colleagues, friends, staff, and family for the unmatched support throughout this process," he wrote in a statement posted on X, the platform formerly known as Twitter.
"It has been an arduous few weeks, and a reminder that the House is as complicated and diverse as the people we represent. The urgency of this moment demands bold, decisive action to restore trust, advance our legislative priorities, and demonstrate good governance. Our House Republican Conference is united, and eager to work."
Forecasting the work ahead, Johnson said he would work to "advance a comprehensive conservative policy agenda, combat the harmful policies of the Biden Administration, and support our allies abroad."
Rep. Mike Johnson will be the least-experienced House speaker in more than a century.
Having only served in Congress since early 2017, Johnson has the least experience in Congress of any speaker in the last 140 years.
At 51 years old, he is also the third-youngest speaker since 1900.
-ABC News' Ben Siegel
Rep. Mike Johnson was elected the 56th speaker of the House of Representatives, winning every single Republican in the chamber.
He prevailed over House Minority Leader Hakeem Jeffries in a 220-209 vote.
