Here's a viewers guide on what to watch for in the final two weeks of the campaign and on election night:
In statewide elections, New Jersey has been a fixture in the Democratic column of late – it's gone Democratic at the presidential level for twenty years and President Obama carried it easily with 57 percent. The state has two Democratic Senators, and Corzine won his initial election by a comfortable ten-point margin in 2005, 53 percent to 43 percent.
But many polls now show Corzine with negative job approval ratings, never a good sign for an incumbent, and the recession has clearly put pressure on him (along with many other governors nationwide).
New Jersey has a Democratic-leaning statewide electorate, where registered Democrats outnumber registered Republicans by around 700,000 voters (though independents still outnumber either party) with a breakdown of Democrats at 34 percent, Republicans 20 percent, and independents /other at 46 percent.
However, in "off year" elections like this one, turnout is especially key, because so many voters stay home. In 2005, only about half of registered voters (49 percent) participated in the governor's election that year. (By comparison, in the 2008 presidential election, 73 percent of voters cast ballots.)
So the story here will probably be decided by which candidate can get more of their would-be voters to the polls.
Breaking down the electorate: Areas and keys to watch
Within this region especially watch Hudson, Union, and Essex counties -- these are among the state's most densely populated, include major cities of Jersey City and Newark, and their Democratic leanings can provide statewide Democratic candidates much the vote margins needed to carry the whole state.
The question is not whether Corzine will win these counties (if past is a guide, he probably will) but by how much. He'll need to run up large margins – as he did in '05 - to try to offset potential trouble throughout the rest of the state.
• In 2005, these three key counties (Hudson, Union and Essex) alone cast nearly one out of every five of all the state's votes.
• Corzine won them combined by more than a 2-to-1 margin, and racked up a whopping 175,000 vote margin in doing so.
• Consider that he won statewide by 239,000 votes, that means those three counties accounted for the lion's share – nearly three-fourths - of his entire statewide win margin.
Whether voters there will turn out is key. Meanwhile, Christie's chances lie partly in hoping to make things a little closer in these counties – not an easy task, but doable if he runs well in their more affluent towns, and if perhaps if voters in these areas are still reeling from the local corruption scandals that have been in their news of late.
Two sizeable counties to monitor for Christie's chances are Bergen and Morris.
Pay particular attention to Bergen, which could be a bellwether this year. Northwest of New York city, it is an affluent suburban county, with plenty of New York commuters, that has gone Democratic in recent years (it went for Corzine in '05 but not as demonstrably as the more urban counties.) It is large -- a quarter-million votes in 2005 -- and a place where Christie might be hoping to run closer to, or even better than Corzine, perhaps by appealing to its higher-income professionals and homeowners, especially on the issues of state and property taxes -- always heated topics in New Jersey, and this year is no exception. It was once a GOP county. But as in other states particularly throughout the Northeast, many of the Garden State's upper-income suburbanites have leaned more Democratic of late.
Morris county, with its wealthy suburbs and growing exurbs further west of New York City, remains solid GOP territory -- Morris has 40,000 more registered Republicans than Democrats, one of the few counties in the state that has such a balance -- and in 2005 Corzine lost here; Mr. Obama lost it as well. Christie will have to drive up turnout and try to widen his Republican margins this year, making electoral hay in a large area favorable to the GOP.
Republicans often do relatively better or run closer to Democrats in many other parts of the state, particularly in the south (including Ocean county, down the shore), and in the northwestern area closer to Pennsylvania -- but none of these areas is as large as the densely-populated parts of the state that tend Democratic.
But underscoring the Democratic patterns, the state's overall demographic composition also presents challenges for any statewide Republican – but also turnout questions for Corzine. With African American and Hispanic support expected to go for the Democrat the question will largely be turnout among these groups (which Corzine will need). Meanwhile, over time, the share of the white population in New Jersey (white voters very narrowly backed McCain here) has decreased.
It's proximity to New York also has a strong impact on the shape of New Jersey elections it terms of money – being covered by the New York and Philadelphia media markets means advertising is extremely expensive for candidates. This could offer some help to Corzine, who has reportedly reached deeply into his own deep pockets for millions to fund his campaign, in the final weeks with television campaigns. Corzine is spending three times as much as his opponent with an outlay of over 16 million.
Another big question in the race remains independent candidate Chris Daggett, who has reached double-digits in some recent public polls. Generally, third party candidates suffer a bit as elections near as voters display a hesitancy to cast a vote for a candidate who trails the major party nominees, and doesn't appear likely to win. However, if his poll numbers remain strong and he garners more attention, that possibility could diminish.
But it is also important to remember that generally, at least some third-party support usually comes from voters who would not otherwise vote at all, which would render his candidacy a more neutral factor.
Check out this report on the campaign so far from CBS News' John Bentley:
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Anthony Salvanto is CBS News Elections Director. Mark Gersh is Washington Director, National Committee for an Effective Congress, and a CBS News Consultant.