THE GOLDILOCKS ZONE
Goldilocks Zone — narrow region around a star where a planet will have just the right conditions to support life.
The Sanders campaign has been existing in a political Goldilocks zone, where he has performed well enough to retain a measurable chance of winning the Democratic nomination, but not well enough to be considered a genuine threat by his opponents or potential opponents. That is not likely to change, unless he wins New York.
The primary characteristic of the political Goldilocks zone is the absence of attack advertising, either from Clinton, who does not want to risk offending Sanders base of enthusiastic supporters, or from Republicans, who see Sanders as a more ideologically extreme candidate and an easier general election opponent.
Here is a link to the type of sustained attack advertising that will begin the moment the Sanders campaign exits the Goldilocks zone.
Boilerplate for the Republican Attack planned for Sanders
(In reference to the above link. I do not agree with the content. It is strictly an example of a line of attack that will be used.)
A complete absence of attack advertising against him has provided Sanders with an unimpeded path upward in the polls, where he has closed to almost even with Clinton in the Democratic race, and leads all three Republican candidates by double digits. However, in evaluating the value of Sanders current lofty position in the polls, it is important to note that Clinton enjoyed a very high approval rating before the Republicans initiated their negative campaign against her with the Benghazi hearings.
Sanders is also in the unique position of being able to tout his rejection of super-pac money, while having the benefits of a de-facto super-pac in Carl Rove's American Crossroads. American Crossroads has waged a relentless attack campaign against Clinton, a significant portion of which spoofs Sanders campaign sites.
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POLLS AND PREDICTION MARKETS — HOW WILL BERNIE SANDERS DO IN NEW YORK?
Bernie Sanders — Look, let me acknowledge what is absolutely true, Secretary Clinton cleaned our clock in the Deep South, no question about it. We got murdered there. That is the most conservative part of this great country. That's the fact. But you know what, we're out of the Deep South now. And we're moving up. We got here, we're going to California, we got a number of large states there. And having won 7 out of the last 8 caucuses and primaries, having a level of excitement and energy among working people and low-income people doing better.
Attributing Clinton's wins to her doing well in "conservative" states is an inaccurate representation of the facts to date, and is not likely to be predictive in evaluating the primaries to come, the next of which is New York.
Nate Silver's article in FiveThirtyEight provides the details, but stated in summary, Clinton's lead over Sanders has nothing to do with with conservative states, it has to do with his poor performance against her in ethnically and economically diverse states.
Clinton is winning states that look like the democratic party
Thus far, Sanders has not demonstrated any degree of competitiveness against Clinton in New York, which is not conservative and bears little resemblance to the far less ethnically diverse states of Wisconsin or Michigan. In New York Clinton's lead, although reduced, remains in double digits.
The prediction markets show Sanders New York odds as descending from a high of 25% to a current level of 10%.