Sen. Kamala Harris Kamala HarrisTexas Democratic official urges Biden to visit state: 'I thought he had his own plane' The Hill's Campaign Report: Biden on Trump: 'He'll leave' l GOP laywers brush off Trump's election remarks l Obama's endorsements A game theorist's advice to President Trump on filling the Supreme Court seat MORE (D-Calif.) is using former Attorney General Jeff Sessions Jefferson (Jeff) Beauregard SessionsRoy Moore sues Alabama over COVID-19 restrictions GOP set to release controversial Biden report Trump's policies on refugees are as simple as ABCs MORE’s expected Senate run to help fuel her sputtering bid for the White House.

Harris, who in a recent Iowa poll had just 4 percent support, sent a campaign email to voters Wednesday night asking for donations that would be split between her presidential campaign and Sen. Doug Jones’s (D-Ala.) campaign.

Jones won the seat formerly held by Sessions in a 2017 special election against Republican Roy Moore Roy Stewart MooreDoug Jones says he will not support Supreme Court nominee before election Roy Moore sues Alabama over COVID-19 restrictions Vulnerable Senate Democrat urges unity: 'Not about what side of the aisle we're on' MORE. ADVERTISEMENT

Harris called Sessions the “extremist architect” of some of the Trump administration’s “most damaging actions," and noted her role as a member of the Judiciary Committee in pushing back on Sessions's confirmation.

“I fought Jeff Sessions every step of the way, voting against his nomination for Attorney General and calling for his resignation when it became clear he lied under oath to protect the President,” Harris wrote to supporters.

“And now that Mitch McConnell Addison (Mitch) Mitchell McConnellDemocratic senator to party: 'A little message discipline wouldn't kill us' House to vote on resolution affirming peaceful transition of power Republican lawyers brush off Trump's election comments MORE has recruited him to run for Senate in Alabama, I need your help in this fight to make sure he never returns to power,” she added.

Sessions is expected to announce plans to run for his former Senate seat on Thursday, multiple sources told The Hill. The deadline to file for the Senate race is Friday.

Several Republicans are already running for the seat, but Sessions has remained popular in Alabama despite his tense relationship with Trump. The primary is slated for March 3.

Sessions would have about $2.5 million cash on hand as a candidate, according to campaign finance reports.