New Hampshire is rubber, Iowa is glue
The "Iowa bounce" is of dubious reliability in both parties (see previous posts), but Republican voters in New Hampshire seem especially resistant to it. Each of the winners in the past four contested GOP caucuses in Iowa has lost the New Hampshire primary a few days later: George H.W. Bush lost to Ronald Reagan in 1980, Robert Dole lost to George H.W. Bush in 1988, Dole lost to Pat Buchanan in 1996, and George W. Bush lost to John McCain in 2000.
Two sets of New Hampshire cities and towns have been consistently anti-Iowa. One group is the bellwether for how the entire state votes, and it seems to be to the right of Iowa voters. Manchester, Derry, and Merrimack are the largest communities in this category. They voted for tax-cutters Reagan in 1980 and Bush in 1988, social conservative (but not evangelical) Buchanan in 1996, and McCain in 2000 (whose crusade against pork-barrel spending arguably put him to the right of "compassionate conservative" Bush, at least in skinflinty New England).
Finally, there are the state’s second and third largest cities, Nashua and Concord. They, too, seem a bit more centrist than the state as a whole in GOP primaries, going for economic conservatives Reagan in 1980 and Bush in 1988 but then moving to social moderates Dole in 1996 and McCain in 2000.