Democratic National Chair Tom Perez. REUTERS/Chris Berry On Saturday, former Labor Secretary Tom Perez narrowly won the election to lead the Democratic National Committee.

The election pitted Bernie Sanders' far-left choice of Rep. Keith Ellison, against Perez, who garnered more establishment support.

Both former President Barack Obama and former Vice President Joe Biden threw their support behind Perez. The DNC election took multiple rounds of balloting to name a clear winner.

President Donald Trump seized the opportunity to knock the election as "rigged" and rehashed old storylines of discord between Sanders and Hillary Clinton.

"The race for DNC Chairman was, of course, totally 'rigged,'" Trump tweeted Sunday morning. "Bernie's guy, like Bernie himself, never had a chance. Clinton demanded Perez!"

A day earlier, Trump mocked the newly elected chairman in a tweet saying "I could not be happier for him, or for the Republican Party!"

On CNN's State of the Union show Sunday morning, Perez responded to Trump's jabs.

"Congressman Ellison and I got a good kick out of that," he said. "Donald Trump, up in the morning tweeting about us. You know, our unity as a party is our greatest strength and it’s his worst nightmare," he continued.

He also made similar accusations about possible rigging during the presidential election.

“Frankly, what we need to be looking at is whether this election was rigged by Donald Trump and his buddy Vladimir Putin,” Perez said.