"It is good to be back home and I'm so proud to be standing here with the next senator from Illinois, Alexi Giannoulias," Obama said in his speach at the Palmer House in downtown Chicago.
"It's wonderful to be here and wonderful to be with Alexi ... he’s my friend ... I know his character and how he loves this country and how committed he is to public service for all the right reasons," Obama said. "He’s not type to put his finger to the wind to suit the political moment ... you can trust him."
Alexi Giannoulias' campaign tweeted the endorsement shortly afterward.
Obama's remarks come at a time when Giannoulias is struggling against his GOP opponent Mark Kirk who, with the help of the RNC, continues to assail democratic state treasurer for his failed family bank and that bank's ties to convicted criminals.
Giannoulias currently holds a narrow lead in polls over Kirk, who has struggled himself with accusations that he made misleading statements about his resume.
Obama's remarks, pitched to the sympathetic ears of local Democrats, included jabs at the past administration.
"Eighteen months ago when I took office, it was the worst recession in our lifetime since the Great Depression," Obama said. Kids in college…tough luck you are on your own. If you were a worker just hanging on ... tough look you were on your own. That was the philosophy of the last administration and their friends in congress…the ownership society, but it really meant you were on your own."
Obama also repeated what has become a familiar refrain: that Republicans are the party of no.
"They haven't come out with a single solitary idea that is different from policies before," Obama said. "Not one that is disceranble from George W. Bush. They are really banking on amnesia that you forgot the recession and deficit started under their watch."
Several times, Obama stressed that his administration has succeeded in creating jobs, and then criticized Rep. Mark Kirk for being against his policies.
"We extended the life of Medicare by 12 years because of health care reform passage," Obama said. "They want to repeal that reform ... Reform protects consumers and the economy. We need this reform, we can't go back, and yet Alexi's opponent wants to get rid of that?
"That's the choice in this election."
Earlier today, President Obama toured a local Ford plant, where he touted the auto bailout plan. Yesterday was his birthday, which he spent at his Kenwood home. He ate dinner last night at Graham Elliot.