Who senators choose, and whether Trump ultimately endorses a candidate in the final hours, could set the tone for Trump’s attempts to assert control over the legislative branch.

Following the election, Republicans will control the Senate with a 53 to 47 majority, but one question remains -- who will become the new Senate majority leader? Outgoing leader Mitch McConnell will remain in Congress but will step aside as the longest serving party leader in history.

Later this week, GOP Senators will select a party leader for the chamber as Mitch McConnell steps down, the first time since 2007.