President Barack Obama holds an edge over Mitt Romney in Florida and Ohio, the two largest battlegrounds in determining who will win the White House on Tuesday, new polls show.

The Wall Street Journal/NBC News/Marist Poll surveys of likely voters released Friday show Mr. Obama maintaining a foothold little changed from four weeks ago, when the Journal surveyed voters in both states just after Mr. Romney's strong debate performance in Denver.

The surveys found the two battling neck-and-neck in Florida, with Mr. Obama drawing 49% support among likely voters to Mr. Romney's 47%.

Mr. Obama held a firmer lead in Ohio—51% to 45%, unchanged from mid-October—where the relatively more buoyant economy and the federal bailout of the auto industry appear to have solidified his support among a wide swath of voters.