In the closing days of the 2018 midterm elections, former President Obama has run a stealth campaign operation designed to bolster African-American and progressive voter turnout in critical races.

Obama has recorded more than 50 get-out-the-vote (GOTV) robocalls, radio interviews and digital ads, and has been featured in newspaper advertisements encouraging Democrats to vote. Without fanfare, he recorded radio ads to run on African American radio shows in Arizona, Florida, Georgia, Illinois, Iowa, Michigan, Missouri, Nevada, New Jersey, New York, North Carolina, Ohio, Oregon, Pennsylvania, Tennessee, Texas, Virginia, Washington, and Wisconsin. He did digital ads for Florida gubernatorial candidate Andrew Gillum and Ohio gubernatorial candidate Richard Cordray.

He even was featured in a newspaper ad for Sen. Joe Donnelly (D-IN) in the Gary Crusader, the hometown paper for the same city where he stumped for the Senator earlier this week.

The ad, paid for by Donnelly for Indiana, features an enormous image of Obama with a message that centers around protecting the Affordable Care Act. “Dear Hoosiers, Tuesday, November 6, your health care is on the ballot,” it reads. “A vote to re-elect Joe [Donnelly] to the United States Senate is a vote to protect health care for yourself, your friends and your family. It’s as simple as that,” the message from Obama continues.

The behind the scenes work by the former president mirrors the approach he and his team took to the Alabama Senate election at the end of 2017. Then, Obama stayed away from the race until the closing day, when he cut a GOTV call for Doug Jones that targeted Alabama’s African-American voters. The call worked, according to Jones’ campaign aides, giving him the needed margins to pull of the surprise victory in the deeply conservative state.

Though Democrats had been fretting over Obama’s absence from the midterm elections as late as this September, the 44th president became a fixture on the trail in the closing weeks. In addition to the work he did behind the scenes, he also appeared at rallies for a number of Senate and gubernatorial candidates, in addition to making voter registration pushes across various digital platforms.