President Trump on Wednesday went on a marathon retweeting spree, amplifying supporters in quick-fire succession who objected to a firefighters union endorsing 2020 Democratic hopeful Joe Biden.

The International Association of Firefighters (IAFF) endorsed Biden this week, just days after Biden announced his 2020 bid. It cited his past support, including for fair pay, overtime guaranteed pay and employee rights.

MEDIA THAT DISMISSED BIDEN NOW SEE HIM AS CLEAR FRONT-RUNNER

But when former Secret Service agent Dan Bongino, a Trump supporter and Fox News contributor, tweeted out that “NONE of the Firemen I know are supporting Joe Biden for President,” Trump retweeted a number of users backing that statement.

“Nope not me either. I’m not voting for crazy Joe. My support is behind @realDonaldTrump in 2020!” one user who caught Trump’s eye said.

“Just the union leadership supports Biden. Members support Trump. This applies to most unions,” another said.

Trump went on to eventually retweet more than 50 supporters within just a few minutes.

However, retweeting dozens of Twitter users is a risky game. One “supporter” who tweeted, “My husband a New York City firefighter for 15 years will be voting Trump 2020 all the way!!” changed their account's name to “F--- Donald Trump” after being retweeted by the White House -- and changed their profile picture to a “Bernie [Sanders] 2020” logo.

In addition to the many retweets, Trump also weighed in on the endorsement himself.

“I’ve done more for Firefighters than this dues sucking union will ever do, and I get paid ZERO!” he said.