The good news for Barack Obama is that support for offshore drilling of oil wells has declined just a bit over the past week. The bad news for the presumptive Democratic Presidential Nominee is that only Democrats are changing their mind.

The latest Rasmussen Reports national telephone survey, conducted June 26, shows that 59% of voters nationwide now support offshore drilling. That’s down three percentage points from a week ago when 62% favored the proposal advocated by Republican nominee John McCain. That difference is small enough that it might be nothing more than statistical noise. However, it is interesting to note the partisan differences.

In both surveys, 87% of Republicans favor offshore drilling. There was virtually no change among unaffiliated voters either. On June 18, 63% of unaffiliated voters favored offshore drilling. On June 26, that number was essentially unchanged at 64%.

However, there was a significant change among Democrats. In the first survey, 41% of Democrats favored offshore drilling while 43% were opposed. After a week of the Obama campaign’s aggressive efforts opposing the concept, just 33% of Democrats favored offshore drilling in the second survey. Fifty percent (50%) of Democrats are now opposed.

Before being asked if they support offshore drilling, the survey participants were told that McCain favors this approach and says it will help bring down prices and that Obama opposes drilling and says it will not reduce gas prices. The survey wording was identical in the June 18 and June 26 surveys. Rasmussen Reports will continue tracking attitudes on this issue periodically over the coming months.

Another survey released earlier this week found that most Americans say it’s likely gas prices could top $5 a gallon this year. Only about a third believe that the price of gas will top $6 or fall below $4 a gallon.

The current survey also found that 50% of voters say it’s likely that allowing offshore drilling will bring down gas prices while 44% disagree.

Sixty-one percent (61%) favor Obama’s proposal for the government to spend $150 billion over ten years developing alternative energy sources. That’s up from 56% a week earlier.

Forty-nine percent (49%) favor building nuclear power plants while 31% are opposed.

Voters are evenly divided as to which is more important—protecting the environment or reducing the price of gas and oil.

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