Democratic presidential candidate Barack Obama and Republican John McCain are trading sharp barbs, as they campaign in critical states six days before the election.

In North Carolina Wednesday, Obama said the country needs change and cannot take four more years of the same old politics and policies.  He said McCain has not been a maverick, but rather a "sidekick" to the unpopular President George Bush.

For his part, McCain told supporters in Florida that Obama's economic proposals will increase taxes and further hurt the economy.  The Arizona senator said he has a plan to cut taxes and create jobs in the United States.

Obama will run a paid, half-hour advertisement on prime-time television late Wednesday.  McCain will be a guest on CNN's Larry King Live late Wednesday.

An average of the latest polls, compiled by shows Obama's lead nationally has dipped by roughly one percent, to just under six percentage points.

Florida and North Carolina voted Republican in the last two presidential elections, but polls show Obama slightly ahead there.  The Republican ticket is also campaigning in Ohio, where Obama leads, and in Indiana, where Obama is ahead in most polls.

McCain's running mate, Alaska Governor Sarah Palin, delivered an energy policy speech in Ohio.  She said if Obama is elected, Democrats will control Washington and do nothing to make the U.S. energy independent.

In Florida, Obama's running mate, Senator Joe Biden, said he believes the clear choice for change is Obama.  He said the United States must reclaim its respect in the world, starting first by ending the war in Iraq.