President Obama recorded a robo-call for Illinois Senate candidate Alexi Giannoulias, asking supporters to vote early.

Obama's call went out Monday to 800,000 Democrats who are likely to vote for Giannoulias, according to the Democrat's campaign. In the call, the president urges them to avoid lines and bad weather by voting early or by mail.

"This is Barack ObamaBarack Hussein ObamaOvernight Energy: Dems ask Pruitt to justify first-class travel | Obama EPA chief says reg rollback won't stand | Ex-adviser expects Trump to eventually rejoin Paris accord Overnight Regulation: Trump to take steps to ban bump stocks | Trump eases rules on insurance sold outside of ObamaCare | FCC to officially rescind net neutrality Thursday | Obama EPA chief: Reg rollback won't stand Ex-US ambassador: Mueller is the one who is tough on Russia MORE calling on behalf of Alexi Giannoulias. With polls showing my good friend Alexi in a close race, your vote is crucial. Early voting is already under way, and I strongly urge you to go vote today. Also, for the first time ever you can vote by mail,” Obama said, according to the script.

Giannoulias is battling against Republican Mark KirkMark Steven KirkHigh stakes as Trump heads to Hill Five things to watch for at Trump-Senate GOP meeting Giffords, Scalise highlight party differences on guns MORE for the seat once held by the president. Obama's call could help boost African-American turnout, which is expected to drop significantly from 2008 levels. Black turnout in Illinois was 17 percent of the vote in 2008. One Democratic pollster recently told The Ballot Box they estimated that this year, the figure could be as low as 11 percent. That could spell trouble for Giannoulias, Gov. Pat Quinn (D) and other candidates, as African-Americans are a solidly Democratic voting bloc in Illinois.