@McGentrix,
The most reliable polls prior to the Iowa caucus showed Trump with a comfortable margin over Cruz, and Rubio a distant third. Instead, Cruz won by a comfortable margin over Trump and Rubio nearly came in second, right on Trump's heels.
The problem with these polls is that they do not include a category for "undecided" -- at least not in the poll results commonly presented on cable news and other popular media.
According to last night's O'Reilly Factor, about a third of Iowa's GOP voters had polled undecided. O'Reilly reported the results of an exit poll of previously undecided voters leaving the Iowa GOP caucus. I seem to recall that about 33% of those voted for Rubio, about 25% voted for Cruz, and just 14% voted for Trump. The rest were split between other candidates.
This would explain the actual caucus results pretty handily: Rubio's surprise overperformance due to a large chunk of previously undecided voters settling for him; and Cruz closing the margin then adding a winning margin, but not as big of a jump as Rubio.
As for New Hampshire, recent news items indicate that among Republicans, undecideds number about 7%. But a third of independents (who are expected to be about 40 percent of primary voters there) are undecided, which means another 13 percent or so in terms of the overall voter population. But only a portion of these self-identify as Republicans, so the percentage of those undecided, Republican leaning voters is smaller still; but they strongly lean towards candidates like Bush and Kasich. Or rather, they did five days ago:
https://www.wbur.org/2016/01/28/new-hampshires-undecided-independent-voters
But now, after Rubio's strong showing in Iowa, these moderate leaning Republican-identifying independents might consolidate their vote in Rubio.
Put together, the undecided Republicans and undecided Republican-leaning independents probably introduce 10-15 % uncertainty. But then you have the possibility of further shifts among weakly decided voters whose candidates did poorly in Iowa but who might be open to Rubio. Plus there is the possibility of a larger than expected voter turnout that includes more moderate leaning independents than expected.
So while it looks like a shoe-in for Trump, it may not be.
As far as I'm concerned, the issue of undecided and weakly decided voters may be the most significant but underreported topic in political news coverage. This may be why some candidates who consistently show low in the polls nevertheless continue to doggedly hang on.