CNN Poll of Polls: All knotted up between Obama and Romney

Washington (CNN) - With six and a half months to go until November's presidential election, it's basically all tied up between President Barack Obama and all-but-certain Republican presidential nominee Mitt Romney, according to an average of the four national surveys conducted entirely after former Sen. Rick Santorum of Pennsylvania suspended his campaign on April 10.

A CNN Poll of Polls compiled and released Wednesday indicates that, on average, 47% of registered voters in the four polls say they back Obama, with 45% supporting Romney, the former Massachusetts governor who is making his second bid for the White House. With each poll having a sampling error greater than Obama's two-point margin over Romney, it's fair to say that the race can be considered a dead heat.

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The announcement by Santorum that he was suspending his campaign was widely seen as the moment when the presidential campaign entered a new phase, moving from a primary fight to a general election battle. Even though former House Speaker Newt Gingrich and Rep. Ron Paul of Texas continue their long-shot bids for the nomination, Romney is now generally considered the presumptive GOP presidential nominee.

The four surveys are from CBS News/New York Times (conducted April 13-17), Gallup's daily tracking poll (conducted April 12-16), CNN/ORC International (April 13-15), and Reuters/Ipsos (April 12-15).

As the CNN Poll of Polls is an average of other surveys, there is no sampling error for the results.

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