Here's another sign that the pressure is mounting on Republican John McCain for a game-changer in tonight's second-to-last presidential debate: A new poll for Time magazine and CNN finds McCain struggling to nail down three battleground states that President Bush carried four years ago.

In North Carolina, Republican red since 1976, McCain is locked in a dead heat with Democrat Barack Obama, with each candidate supported by 49 percent of likely voters. Bush won the state by 12 points in both 2004 and 2000.

McCain enjoys a narrow lead in Indiana, which has not supported a Democratic presidential nominee since LBJ in 1964, with 51 percent of likely voters to 46 percent for Obama. Consider that Bush carried Indiana by 21 percentage points in 2004 and 16 points in 2000.

And in the battleground of battlegrounds, Ohio, McCain trails Obama by three points among likely voters, 47 percent to 50 percent. Bush won the state by the narrowest of margins in both his elections, and the state put him over the time in the Electoral College four years ago.

Obama also holds a statistically significant lead of 8 points in New Hampshire and 5 percentage points in Wisconsin, two battleground states that Democrat John Kerry won in 2004. The McCain campaign said it was targeting both states after pulling out of Michigan late last week.

Results are based on telephone interviews conducted Oct. 3 through Monday. They are subject to a statistical margin of error of plus or minus 3.5 points in New Hampshire, Ohio and Wisconsin; and 4 points in Indiana and North Carolina.

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