ATLANTA — Democrat Jon Ossoff officially announced his 2020 run for Senate on Tuesday morning, taking aim at incumbent Sen. David Perdue by calling him a "caricature of Washington Corruption."

Ossoff, who previously made a failed bid for Congress in the 2017 special House election in Georgia's 6th District, first announced his intentions on MSNBC on Monday night.

In his official announcement, he said his "campaign will expose" Perdue.

"Georgia is now the most competitive state in the country, and the Senate majority will be decided in Georgia," Ossoff said.

Ossoff has the endorsement of Rep. John Lewis, and the long-serving Congressman praised his "talent, integrity and commitment to our community" in a statement.

"Jon has a proven record fighting for justice and exposing corruption, and I will do everything in my power to support Jon's election to the United States Senate," Lewis said.

Ossoff said he was "honored to receive this endorsement from my hero and my mentor."

RELATED: Democrat Sarah Riggs Amico announces bid for U.S. Senate

The campaign also announced two senior personnel: Campaign Manager Ellen Foster and Political Director Steven Parker.

Federal Election Commission financial filings from late March show the Jon Ossoff For Congress campaign committee still had more than $400,000 in cash on hand.

Ossoff joins Sarah Riggs Amico, who lost last year's election for lieutenant governor, in the Democratic field. Speculation has also surrounded Rev. Raphael Warnock of Ebenezer Baptist Church for years in local and national publications about his potential interest in a Senate run.  

Stacey Abrams, widely seen as Georgia's leading Democrat, has ruled out a Senate run.

The Republican party appeared to welcome the competition - in a statement to 11Alive the National Republican Senatorial Committee the group wrote "Democrats in Georiga are still without a top-tier U.S. Senate candidate," while taking a dig at Ossoff. 

"Failed congressional candidate Jon Ossoff's serial resume inflation and extreme left-wing views will fit in with the rest of the crowded Democratic primary but will stand in sharp contrast to David Perdue's positive record of delivering results for all of Georgia," said NRSC spokesperson Nathan Brand.

Perdue is up for re-election in one of two Senate races in Georgia next year. The other will be a special election to fill out the rest of Sen. Johnny Isakson's term after the long-serving Republican announced he would be retiring at the end of the year due to ongoing health concerns.

In announcing his Senate run, Ossoff outlined campaign themes that included defending abortion rights - a particularly contentious issue in Georgia with the "heartbeat" law set to take effect next year - and prioritizing climate change, health care and voting rights.

"We believe the battle that began in Georgia in 2017 will be won in Georgia in 2020 when we flip the Senate and win the White House," he said.

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