Jackson is seeking ninth term in Congress. He claims he has support from Emanuel.
The mayor said Tuesday he worked with Jackson when both of they were in Congress. He has also served with Halvorson, whom he helped recruit to run for Congress.
"I have a lot of respect for Congressman Jackson. We worked together as colleagues, served together for 6 years. He is a good Congressman. Debbie was a good Congressman. And I'll make my statement when it's necessary. I don't get drawn into politics when I don't think it's the time or the place, Mayor Emanuel.
An official with president Obama's campaign said the president has not formally endorsed either candidate, but Mr. Obama did tell Jackson he would support the congressman.