In New Jersey's U.S. Senate campaign, Republican Tom Kean, Jr. (R) now leads Senator Robert Menendez (D) by just three points, 40% to 37%.

Last month, Kean, the son of the former governor, led 43% to 36%. But most of our polls of this race have shown toss-ups.

Menendez is the incumbent, but an appointee, and a recent one. He was installed in January 2006 when fellow Democrat Jon Corzine left the U.S. Senate to become the state's Governor.

Normally, an incumbent polling consistently below 40% would be considered very vulnerable. Certainly, it's not good news for the Democrat. However, Kean has a political reality of his own to worry about: the political gravity in New Jersey generally favors Democrats. Our latest polling finds that the large number of undecided voters uniformly tend to trust Democrats more than Republicans on the issues.

For example, 48% of undecideds trust Democrats more than Republicans on national security; only 30% trust the GOP more. On energy policy, 62% trust Democrats more. Democrats are also favored on other issues. With no strong preference for either candidate, fence-sitters may end up going with the party they're most comfortable with.

Another factor for Kean to contend with is that only 27% of New Jersey voters approve of the way that President Bush is doing his job. On each of five issues we asked about, at least 40% of Garden State voters believe the President is doing a poor job. On Iraq, the number saying he is doing a poor job jumps to 60%.

A plurality of undecided voters regard the President's performance as Poor on each issue--the economy, national security, immigration, energy policy, and Iraq.

The rolling average of the last three Rasmussen Reports election polls in New Jersey shows a very similar result to the current survey with Kean ahead 41% to 37%. It's interesting to note that more than a fifth of New Jersey voters have remained undecided throughout the campaign to date. Given the Menendez cash advantage that's another cause for the Kean campaign to be concerned.

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