WASHINGTON  A majority of American voters say that the furor over the relationship between Senator Barack Obama and his former pastor has not affected their opinion of Mr. Obama, but a substantial number say that it could influence voters this fall should he be the Democratic presidential nominee, according to the latest New York Times/CBS News Poll.

At the same time, an overwhelming majority of voters said candidates calling for the suspension of the federal gasoline tax this summer were acting to help themselves politically, rather than to help ordinary Americans. Mr. Obama’s rival for the Democratic nomination, Senator Hillary Rodham Clinton, has made the suspension of the gas tax a centerpiece of her campaign in recent days.

In the survey, taken in the days leading up to the primaries on Tuesday in Indiana and North Carolina, Americans were divided over the merits of the gasoline-tax suspension, which has also been backed by the presumptive Republican nominee, Senator John McCain, and condemned by Mr. Obama as political gimmickry.

Mrs. Clinton and Mr. Obama spent the final Sunday before the two primaries debating the gas-tax holiday and other issues on morning talk shows and in events across Indiana.