Don't take my word for it. Read all about it at Factcheck.org. Obama's first general election ad, called "Country I Love", sounds like he was responsible for three bills to "move people from welfare to work", "cut taxes for working families", and "extend health care for wounded troops".
Turns out the first two were for Illinois residents only, during his one and only term in THAT legislature. The first he was an original co-sponsor of and the second he was added as a co-sponsor after others had done the work.
The third was in the U.S. Senate but is a bill he neither sponsored or co-sponsored.
What a liar, but then when your resume is paper thin, and you've only served 143 days in the U.S. Senate and spent the rest of the time campaigning for the job you want next, it's hard to rack up substantial Senatorial accomplishments.