The gap between the two major presidential contenders has narrowed to 5 percentage points in New Jersey, as some of Barack Obama’s support appears to have slipped off into the undecided column over the past month.

The latest Rasmussen Reports telephone survey of New Jersey voters, taken Monday night, shows Obama ahead of Republican candidate John McCain 44% to 39%. Last month, the Democratic hopeful had a 48% to 39% lead over his GOP rival.

Now 11% of voters describe themselves as undecided, up from 6% in early June. Five percent (5%) favor some other candidate.

If leaners are included, Obama leads McCain by an even narrower 47% to 44%. Leaners initially indicate no preference for either major candidate but indicate that they are leaning towards either McCain or Obama. Nationally, Obama continues to hold a modest lead over McCain in the Rasmussen Reports daily Presidential Tracking Poll. Voters perceive their priorities on Iraq are the biggest difference between McCain and Obama. Other key stats on Election 2008 are continuously updated at Obama McCain By the Numbers.

While the Presidential race has tightened in the Garden State, incumbent Democratic Senator Frank Lautenberg has a growing lead over Republican challenger Dick Zimmer.

New Jersey voters clearly disagree with their other Senator, Robert Menendez, who is promoting a bill to maintain the ban on offshore oil drilling. Sixty percent (60%) say such drilling should be allowed, and 53% think it is likely to cause gasoline prices to go down.

Last month Obama’s then-growing lead was linked in part to Hillary Clinton voters moving into his column. The June survey was conducted 24 hours after Obama had reached the number of delegates needed to capture the Democratic presidential nomination.

Women, a key voter bloc at play in the presidential campaign, continue to support the Democrat (52%) far more than his Republican opponent (28%). Fifty-three percent (53%) of female voters voiced support for Obama a month ago, but McCain has fallen significantly from 34%. Those voters have moved into the undecided column.

Men, on the other hand, have shifted even more dramatically to McCain. Now 54% of male voters back McCain, up from 46% in early June, while 34% favor Obama, an eight percentage point decline from a month ago. Only 6% of men are undecided as opposed to 15% of women.

While both McCain and Obama have locked up more than 70 percent of the voters in their respective parties, unaffiliated voters prefer the Republican candidate to his Democratic opponent 47% to 33%.

Rasmussen Markets data gives Obama an % chance of winning New Jersey’s 15 electoral votes this November. George H.W. Bush in 1988 was the last Republican presidential candidate to carry New Jersey where no Republican has won a statewide office since 1997. John Kerry carried New Jersey over President Bush -- 53% to 46% -- in 2004.

Obama and McCain continue to be regarded favorably by the majority of New Jersey voters, although both candidates have lost some ground since June.

Forty-three percent of New Jersey voters rate economic issues as most important in the current political cycle, while 23% say national security is their number one concern.

President Bush’s approval rating is up slightly, with 27% of New Jersey voters saying he is doing a good or an excellent job. But fifty-two percent (52%) say he's doing a poor job, down two percentage points from a month ago.

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