One of the most important things that Senator McCain must do, is to secure a decent share of “undeclared” (i.e., independent) NH voters, who can vote in either primary- and don’t have to decide, until Tuesday.  According to the Concord Monitor, in this story detailing the predictions of the highly respected Secretary of State, William Gardner:

Gardner forecasts record turnout

Submitted by Primary Monitor on Fri, 2008-01-04 15:44.

Secretary of State Bill Gardner is predicting a record half million voters will turn out for Tuesday’s presidential primary. Gardner is predicting 260,000 residents will vote in the Democratic primary and 240,000 will vote in the Republican primary. He predicts that 150,000 undeclared voters — who can choose which primary to vote in — will cast votes. Of those, he thinks 90,000 will choose to vote in the Democratic primary and 60,000 in the Republican.

He predicts that 50,000 New Hampshire residents will register to vote on election day. The previous record of 396,000 voters was set in the 2000 primary.

- The Associated Press

UPDATE: Doing the math … Gardner is predicting that undeclared voters will cast about 35 percent of the ballots in the Democratic primary and 25 percent of the ballots in the Republican primary. Those are now benchmarks against which to compare the samples in opinion polls. (Overall, he’s predicting that 30 percent of the voters will be undeclared voters, 34 percent will be Democrats and 36 percent will be Republicans. And that the undeclared voters will break 60-40 for the Democratic race.)

The key for McCain will be for him to attract as many independent voters as possible, to vote for him in the GOP primary, rather than selecting Democratic ballots.   Essentially, he has to do the same thing that Huck did in Iowa.  Mitt’s ground operation in Iowa, by all accounts, did a fantastic job.  They hit (and might have exceeded) their vote total targets.  However, they were deluged by the flood of pro-Huckabee voters that showed up at the polls, which were far greater than they expected.  For McCain, it is essentially the same thing (although in his case, his task is more complicated, because he has to persuade voters to sacrifice their vote in the Democratic primary in order to cast one for him, which Huck did not need to do in Iowa.)  If McCain can successfully expand the pool of Republican primary voters, he should be able to prevail.   One factor is that most of Romney’s support comes from Republicans who describe themselves as very conservative.  Obviously, very conservative voters are likely to be disproportionately represented in a Republican primary - but by definition, their numbers are finite.  In contrast, there are far more moderate Republicans and independents who could potentially vote. 

To summarize, McCain has a potentially higher ceiling from which to draw support.  He can add a substantial number of voters to the primary electorate, due to his appeal to those larger groups.  In contrast, Mitt has more of a ceiling, because he can’t expand the number of very conservative Republicans, beyond what it already is.

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