Obama and McCain in fuel price row
Barack Obama has appealed to American voters struggling with the skyrocketing price of petrol, casting Republican rival John McCain as a Washington insider who is in part responsible for the country's dependence on foreign oil.
Speaking at a rally in Ohio, the Democratic presidential candidate said he agreed with Mr McCain's recent comment that the dependence "has been 30 years in the making, and was caused by the failure of politicians in Washington to think long-term".
Mr Obama noted that Mr McCain has been in Washington for 26 of those years.
In that time, Mr Obama said, "he has achieved little to help reduce our dependence on foreign oil" and "has been a part of that failure" to address the energy crisis.
Voters worried about the economy have made the spiking cost of fuel one of the top issues in the presidential campaign. Americans have appeared to be more receptive to some of Mr McCain's proposed solutions, including increased oil drilling in the United States.
Mr McCain recently changed his position on the quarter-century US ban on drilling for oil and gas in offshore waters, saying states should be allowed to open those resources to oil companies if they wished.
He has also called for a major push to develop nuclear power and said he would give a 300 million US dollar (£150m) prize to the developer of a battery capable of efficiently powering cars.
Mr Obama has focused on increased spending for alternative energy sources funded in part by taxes on excess oil company profits and closing a legal loophole that he says has led to speculation on energy markets and driven prices to record levels.
In his first negative ad of the general election campaign aired this week, Mr Obama called Mr McCain "part of the problem" of high petrol prices, trying to parry Republican criticism of his own energy policy.
The 30-second commercial was a direct response to a Republican Party ad. The Republican spot - airing at a cost of 3 million dollars in four states - accuses Mr Obama of offering no new solutions to solve high petrol prices and global warming.