President Donald Trump on Joe Biden's 2020 run: 'He's not the brightest lightbulb in the group'

WASHINGTON – President Donald Trump "welcomed" former Vice President Joe Biden to the 2020 presidential election Thursday by insulting his intelligence and promising a "nasty" race for the White House.

Taunting his opponent as "Sleepy Joe," Trump tweeted: "I only hope you have the intelligence, long in doubt, to wage a successful primary campaign. It will be nasty - you will be dealing with people who truly have some very sick & demented ideas. But if you make it, I will see you at the Starting Gate!"

Biden laughed off the tweet, telling reporters during a visit to a restaurant in Wilmington, Delaware: "Everybody knows Donald Trump."

Later Thursday, Trump told Fox News that he didn't know who would end up becoming the Democratic nominee for president but said Biden was a name that people knew. But, he added on Biden's candidacy, "He's not the brightest lightbulb in the group."

Trump's remarks followed an announcement video in which Biden cast the prospect of a second Trump term as a threat to American values. He cited, in part, Trump saying there were fine people on "both sides" of the violent clashes between counter-protesters and white nationalists in Charlottesville, Virginia, in 2017.

"If we give Donald Trump eight years in the White House," Biden said, "he will forever and fundamentally alter the character of this nation, who we are, and I cannot stand by and watch that happen."

More: Joe Biden uses Charlottesville as motivation for 2020 run: 'We are in the battle for the soul of this nation"

More: Who is running for president in 2020? An interactive guide

It's not unlike the president to offer greetings to new 2020 contenders. When Vermont Sen. Bernie Sanders announced his candidacy in February, Trump said in a tweet, "Crazy Bernie just entered the race. I wish him well!"

On April 17, Trump predicted it would be either Biden or Sanders who would challenge him in 2020.

"I believe it will be Crazy Bernie Sanders vs. Sleepy Joe Biden as the two finalists to run against maybe the best Economy in the history of our Country (and MANY other great things)! I look forward to facing whoever it may be. May God Rest Their Soul!" he tweeted.

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This article originally appeared on USA TODAY: President Donald Trump on Joe Biden's 2020 run: 'He's not the brightest lightbulb in the group'