Barack Obama‘s lead over John McCain has widened in four key battleground states during the past three weeks, writes the Washington Post.

“Obama holds double-digit margins over McCain in Minnesota, Michigan and Wisconsin and carries a nine-point advantage over his Republican rival in Colorado, according to polling conducted by Quinnipiac University for and the Wall Street Journal.

“Obama’s ascendancy in these key states mirrors his growing lead in national polling. The latest Washington Post/ABC News survey put Obama at 53 percent to McCain’s 43 percent, while the daily Gallup tracking poll showed Obama holding a similar lead of 51 percent to 41 percent on Monday.

“The latest polling confirms that the financial crisis and stock market crash that has gripped Wall Street and Washington over the past month has increased the importance of economic matters to voters — particularly in the industrial Midwest — and accrued almost exclusively to Obama’s benefit.”

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