President Donald Trump has challenged Ken Paxton and James Talarico to face off in a debate in the Texas Senate race. Trump has been pushing for a head-to-head contest between the two candidates.

Trump has taken to calling Talarico “Talafreako,” a nickname the Democrat’s campaign is now printing on T-shirts. Talarico was absent from the campaign trail for more than a week, prompting attacks from Trump and Paxton supporters; he later said he had the flu.

Debates can be decisive in tight races, and Trump’s call raises the pressure on both camps to agree to terms. Neither campaign has confirmed a debate schedule yet.

Texas has not elected a Democrat to the Senate in decades, but both parties are pouring money into the race. The outcome could help decide control of the chamber.

Paxton has served as Texas attorney general since 2015, while Talarico is a state representative known for his debate performances. The winner will face the other party’s nominee in November in a race that could decide Senate control.