Because of voter registration gains by Democrats, New York Sen. Hillary Clinton or Illinois Sen. Barack Obama would have an advantage in the November general election over the presumptive Republican nominee, Arizona Sen. John McCain -- but not enough of an advantage to win the election outright, the news site reported.

An analysis by the newspaper Roll Call found four states with 74 electoral votes among them -- Arkansas, Florida, Ohio and Pennsylvania -- would be easier for Clinton to win. Six states with 49 electoral votes -- Arizona, Colorado, Iowa, Nevada, New Mexico and Virginia -- should be easier for Obama to win, the report said.

Stateline projected the presidential election would likely be decided by a group of "toss-up" states, including Iowa, Virginia, New Mexico and Ohio.

Overall, the number of states up for grabs this year makes the 2008 presidential election the most wide open White House contest in at least 50 years, Stateline said.