Those 15 states have roughly one-third of the nation's population, so the results will be a good indicator of voter sentiment.
Polling experts say it is notoriously difficult to pin down the news media's influence on voter sentiment.
"And what they are doing is playing with voter sentiments in an irresponsible fashion."
CNN has hired more than 1,000 people to help it conduct its own survey of national voter sentiment.
Much of the sour voter sentiment around the country stems from higher taxes in general.
But the voter sentiment shifts reflected in the surveys also indicate that the contest is far from over.
And because the candidates pay the $25-a-head entry fee for voters, it is not even an impartial indication of voter sentiment.
Having played a decisive role in the last presidential election, Ohio is seen as a barometer of voter sentiment nationally.
Such a move might occur if party leaders felt confident about voter sentiment swinging back in their favor.
The City Council has set an advisory ballot measure to gauge voter sentiment next year.