Democratic presidential hopeful Barack Obama criticized his Republican opponents on Thursday for supporting President George W Bush's policies, reported dpa.
The Obama campaign said the speech by John McCain's vice presidential candidate, Alaska Governor Sarah Palin, at the Republican convention Wednesday night undermines their effort to portray themselves as candidates of change.
"The speech that Governor Palin gave was well delivered, but it was written by George Bushs speechwriter and sounds exactly like the same divisive, partisan attacks we've heard from George Bush for the last eight years," said Bill Burton, the spokesman for the Obama-Joe Biden campaign.
"If Governor Palin and John McCain want to define `change as voting with George Bush 90 per cent of the time, thats their choice, but we dont think the American people are ready to take a 10 per cent chance on change," Burton said.
The Obama camp fired back hours before McCain was set to accept the Republican nomination in a speech Thursday evening to conclude the party's convention in St Paul, Minnesota.
Palin, who was a relatively unknown politician from one of the least-populated US states, spoke at the convention Wednesday night in what was seen as a speech to introduce her to Americans.
She touted herself as a reformist who understands the needs of working class families and said McCain has a track record of getting things done - a shot at Obama's perceived lack of experience.
"In politics, there are some candidates who use change to promote their careers, and then there are those like John McCain who use their careers to promote change," Palin said to an enthusiastic crowd.