Obama ahead in polls
President Obama speaks to supporters on September 17, 2012 in Columbus, Ohio. President Obama spent the day in Ohio campaigning in Cincinnati and Columbus. (Photo by Matt Sullivan/Getty Images)

President Obama has sizable leads in Colorado, Iowa and Wisconsin according to new NBC News/Wall Street Journal/Marist College surveys, the latest sign of his strong advantage entering the final stages of the campaign.

Related: Obama reaches 50 percent nationally

Obama leads Mitt Romney 50 percent to 42 percent in Iowa, 50 to 45 in Colorado and 50 to 45 in Wisconsin. The numbers mirror the president’s advantages in Virginia, Ohio and Florida and show the challenges for Romney. He must come from behind and capture some of these swing states to win in November.

These state numbers come as the Pew Research Center released a survey that showed Obama ahead 51 to 43, in line with other surveys suggesting Obama is near or beyond 50 percent support.

“With an eight-point lead over Mitt Romney among likely voters, Barack Obama holds a bigger September lead than the last three candidates who went on to win in November, including Obama four years ago. In elections since 1988, only Bill Clinton, in 1992 and 1996, entered the fall with a larger advantage,” Pew wrote.

The Pew survey showed Obama ahead by 45 points over Romney among Hispanics, 90 with African-Americans, 26 among voters under age 30 and 19 among women.