Florida (United States), Oct. 21: Democratic presidential candidate Barack Obama on Monday accused his republican rival John McCain of launching an "ugly" bid to stave off defeat, while campaigning along with Hillary Clinton in the crucial swing state of Florida.

With just 15 days to go before the election, Obama implored supporters to flood early voting stations in the state and vote for him rather than McCain.

In 2000 and 2004, the state had voted Republican.

Obama accused McCain of stooping to cynical small politics in a desperate attempt to stage an 11th-hour rescue for his faltering presidential hopes.

"In the final days of campaigns, the say-anything, do-anything politics too often takes over," Senator Obama told 8000 supporters in a rally in Tampa, before travelling on to stump with Senator Clinton for the first time since June in Orlando.

"We''ve seen it before and we''re seeing it again - ugly phone calls, misleading mail, misleading TV ads, careless, outrageous comments," Obama said.

"It''s getting so bad that even Senator McCain''s running mate denounced his tactics last night. You really have to work hard to violate Governor Palin''s standards on negative campaigning."

Palin, who has launched some of the most stinging attacks against Obama, was quoted by The Age and news agencies as saying that if she were in charge, she would not rely on "the old conventional ways of campaigning, that includes those robo-calls".

The McCain campaign has been using automated calls to question Senator Obama''s character and values in a bid to drive up his negative ratings in swing states.

Obama, basking in former Republican Secretary of State Colin Powell''s high-power endorsement, has raked in a staggering 150 million dollars in fund-raising in September.

He also leads national polls.

McCain, on the other hand, warned "nothing is inevitable" despite his huge cash deficit and polls which give Obama the lead two weeks out.

"We never give up, we never quit," the Arizona senator told cheering supporters in Belton, Missouri.

He once again raised questions about Obama''s capacity to lead, ironically echoing attack lines that Hillary Clinton had used against Obama during the primaries earlier this year.

"What America needs in this hour is a fighter; someone who puts all his cards on the table and trusts the judgment of the American people," McCain said.

Clinton, appearing at a rally with Obama, said McCain just represented a prolongation of the presidency of George Bush.

The latest daily tracking poll of registered voters by Gallup showed Senator Obama expanding his lead to 11 points and the Democrat was up nine points in the likely voters category, perhaps reflecting General Powell''s impact on the race.

The daily Rasmussen survey however, has McCain trailing Obama by 50 percent to 46 percent of voters nationwide.

A Suffolk University poll found Obama leading by 51 percent to 42 percent in Ohio. McCain is up by a single point in Missouri, a traditional Republican state threatening to go Democratic.

Obama is expected to spend much of the week in Florida, Virginia and Iowa, all Republican strongholds, hoping to convert his lead on the electoral map into a thumping victory. (ANI)