US election battle shifts to Florida

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The rivals for the White House are starting to focus on the key Southern states won by George Bush in 2004, with just 18 days to go before the vote, according to BBC.
John McCain, who is trailing in the opinion polls, must hold Virginia, North Carolina and Florida to have a realistic chance of being elected.
Mr McCain campaigned in Florida on Friday, issuing warning on taxes.
He said his opponent Barack Obama, who goes to Florida next week, "could use a few more tough questions".
"Hold onto your wallet," he said, claiming that Mr Obama could not be relied upon to fulfil any tax-cutting pledges.
He also defended his use of "Joe the plumber", a voter who was used by Mr McCain as an example of how people could suffer under Barack Obama's tax plans.
"Last weekend, Senator Obama showed up in Joe's driveway to ask for his vote, and you know what Joe did? He asked Senator Obama a tough question. I'm glad he did," said Mr McCain.
Mr McCain is also planning on drawing on the help of Senator Joe Lieberman, who is popular with Jewish voters in the state.