1RIVALS FOR OBAMA ' S EX-SENATE SEAT KEEP UP ATTACKS .
2The two candidates running for President Barack Obama 's former Senate seat continued to attack each other on issues of character in their second debate here Tuesday .
3Alexi Giannoulias , the Democratic state treasurer , and Rep. Mark Steven Kirk , a five-term Republican congressman , met in an hourlong debate moderated by George Stephanopoulos , the anchor of `` Good Morning America . ''
4The candidates sparred over their pasts before discussing immigration , jobs and corruption at the debate at the ABC studio in downtown Chicago .
5The candidates are locked in a close race , according to polls , with two weeks left until Election Day .
6The campaign has been increasingly negative , with each candidate attacking the other 's background in television ads .
7Giannoulias returned to an issue that arose in the first debate , repeatedly asking Kirk whether he had ever been shot at during his time in the Naval Reserve .
8Kirk has acknowledged that he has made misleading statements about his service .
9`` Congressman , it 's a simple question , were you shot at or not ? ''
10Giannoulias said .
11Kirk replied that Giannoulias had no right to criticize him because he had not served in the military .
12`` The ultimate irony is that a man who spends most of his campaign for the Senate criticizing my military record and yet he never served a day in uniform himself , '' Kirk said .
13Both candidates have faced questions about their pasts .
14Giannoulias has received criticism for his time as a senior loan officer at his family 's bank , which was seized by federal regulators this year .
15Reports have found that the bank made loans to people with connections to organized crime .