Two decades after John Thune ignited his political brand by knocking off Democratic Senate Leader Tom Daschle in South Dakota’s momentous 2004 U.S. Senate race, he will assume the Republican leadership role himself.

Thune, who is 63 and in his fourth Senate term, has promised to work closely with Trump despite differences the two have had over the years.

It was the first seriously contested Senate Republican leadership election in decades. Three senators were competing to succeed longtime GOP leader Mitch McConnell of Kentucky, when he steps down from the post at the beginning of next year and Republicans take back the Senate majority.