Rep. Julia Letlow, R-La., the Trump-backed candidate primary challenging incumbent Sen. Bill Cassidy, R-La., tells Fox News Digital President Donald Trump’s endorsement is "the most powerful…in the world."

President Donald Trump bashed Sen. Bill Cassidy, R-La., who is running for reelection, in a Saturday morning Truth Social Post, calling him a "sleazebag" and "a terrible guy." 

Sen. Bill Cassidy, R-La., is facing pressure from President Donald Trump-backed challengers as he seeks renomination in Saturday’s primary. (Chip Somodevilla/Getty Images; Tyler Kaufman/Getty Images)

Trump on Friday endorsed Cassidy's primary challenger, Rep. Julia Letlow, R-La.

On the morning of the primary, Trump on Saturday further urged Lousiana voters to back Letlow.

CLICK HERE TO DOWNLOAD THE FOX NEWS APP

This is a developing story. Please check back for updates.

Get the latest updates on the Trump administration and Congress, exclusive interviews and more Fox News politics content.

By entering your email and clicking the Subscribe button, you agree to the Fox News Privacy Policy and Terms of Use, and
        agree to receive content and promotional communications from Fox News. You understand that you can
        opt-out at any time.

Subscribed

You've successfully subscribed to this newsletter!