The Republican Party formally nominated Donald Trump for president of the United States Tuesday, capping a roller-coaster campaign that saw the billionaire tycoon defeat 16 White House rivals.

“It’s my honor to be able to throw Donald Trump over the top in the delegation count tonight,” the candidate’s son Donald Trump Jr told delegates at the Republican National Convention which erupted in cheers and applause.

Trump is expected to formally accept the nomination in a speech on Thursday, before facing off against Democrat Hillary Clinton in the November election battle.

CLEVELAND, OH – JULY 19: Donald Trump Jr. (2nd-L) along with Ivanka Trump (C) and Eric Trump (R), announce take part in the roll call in support of Republican presidential candidate Donald Trump on the second day of the Republican National Convention on July 19, 2016 at the Quicken Loans Arena in Cleveland, Ohio. An estimated 50,000 people are expected in Cleveland, including hundreds of protesters and members of the media. The four-day Republican National Convention kicked off on July 18. Joe Raedle/Getty Images/AFP