By Steven Thomma | McClatchy Newspapers

WASHINGTON — Hunger for change is helping Barack Obama hold a small lead in four battleground states, a new poll indicates today.

The numbers:

• In Colorado, Obama leads John McCain 49-45. He had trailed in the last survey there before the conventions;
• In Michigan, Obama leads 48-44. He also led by 4 points before;
• In Minnesota, Obama leads 47-45. He also led by 2 points before;
• In Wisconsin, Obama leads 49-42. He had led by a wider margin before.

The key reason for Obama's edge appears to be that voters wants change, and by wide margins see Obama as the more likely agent of change than McCain. They preferred Obama to change things by margins ranging from 19 to 24 points.

"With a lousy economy, an unpopular war and an even less popular Republican president, it's difficult to find voters who don't want change," said Peter Brown, assistant director of the Polling Institute at Quinnipiac University, which conducted the polls in conjunction with the Wall Street Journal and washingtonpost.com.

"Sen. Obama...has made himself the candidate of change with a dual track strategy: joining Sen. McCain at the hip with President George Bush, who symbolizes the status quo, while sharply defining himself and his policies as the antithesis of the president.

"The Wall Street meltdown while these polls were in the field probably fed the public desire for change and seemed to benefit Sen. Obama."

The polls each has a margin of error of plus or minus 2.6 or 2.7 percentage points.