Barack Obama’s lead over John McCain in Minnesota has now grown to 18%, all at the expense of voters who have moved out of the Republican’s column, according to the latest Rasmussen Reports telephone survey.

For the second month in a row, 52% back Obama, compared to 34% who now support McCain. But last month McCain had the support of 39% of Minnesota voters.

When leaners are factored in, Obama leads McCain by 17% -- 54% to 37%.

Obama has maintained a 13- to 15-point lead in four out of the previous five monthly polls. The only exception came in mid-March – soon after McCain wrapped up his party’s nomination and the controversial remarks of Obama’s pastor, Jeremiah Wright, were first reported -- when McCain was within four points of his Democratic opponent.

While Obama and McCain maintain the support of more than eight out of 10 members of their respective parties, both have lost ground among unaffiliated voters, 25% of whom remain undecided. Obama leads McCain 45% to 23% among the unaffiliated, but both are down 7% from early June.

The Democrat outpolls his Republican opponent nearly two-to-one among women voters 57% to 30%. He also has the support of 45% of men versus 39% who back McCain.

Nationally, Obama and McCain are very competitive in the Rasmussen Reports daily Presidential Tracking Poll.

The favorability ratings of both McCain and Obama continue to climb in Minnesota. McCain is regarded favorably by 56% of voters, up from 54% in June, while 65% view the Democratic candidate in a similar light, a 5% increase since last month.

Forty-one percent (41%) of Minnesota voters regard the economy as the most important issue in the presidential campaign, with national security, the key issue in the 2004 election cycle, now ranked first by only 20%.

Unlike the majority of voters nationwide, 50% in Minnesota say it is more important to protect the environment than to reduce the record price of gas at the pump. Only 30% say reducing gas prices is more important.

While 48% favor overturning the ban on offshore oil drilling, a position first espoused by McCain and since endorsed by President Bush, 33% disagree. Again, unlike the majority nationwide, half of Minnesota voters (50%) do not believe offshore drilling is likely to drive down the price of gas. Only 41% believe it is likely to have that effect.

Forty-seven percent (47%) oppose drilling in the Arctic National Wildlife Refuge (ANWR) in Alaska, but 40% are in favor of it. Democrats in Congress have consistently opposed offshore drilling and the opening of ANWR for environmental reasons.

However, a majority of Minnesota voters (51%) oppose returning to 55 mph speed limits, and even more (56%) say that’s not the way to reduce gas and oil prices. Those figures are close to the national average.

Only 24% think President Bush is doing a good or excellent job, down from 30% last month, while 58% rate his performance as poor. Nationally, the president continues to set record low ratings for job performance.

This survey was conducted in partnership with Fox Television Stations Inc.

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