Julia Letlow and former congressman John Fleming are set to square off for the Republican runoff for Louisiana's U.S. Senate seat.
The race picks a successor to retiring Senator Bill Cassidy.
Letlow has the support of former President Donald Trump.
Fleming says he is a challenger to the Trump‑backed candidate.
Voters have observed both candidates travel across the state.
The contest will demonstrate the extent of sway Trump still has with Louisiana GOP voters.
The runoff will choose who will occupy in the Senate next.