Clinton gave a convincing endorsement of Obama and his policies.
Former President Bill Clinton is a very popular president and the U.S. economy did pretty well during his administration. Moreover, he was known for making bold moves that helped cut the deficit by raising taxes. Clinton was assertive about the fact that things will turn around and any disillusioned voter out there should not lose faith on their choice of Obama back in 2008.
As impressive as Clinton's speech was, the other side was quick to point out perceived flaws. A lot of these criticisms were valid. The economy did start tanking since the end of the second term of Bill Clinton's stay in office and there was a 1999 repeal of the Glass-Steagall Act that played a part in the 2008 financial crisis.