CNN  — 

Political buffs have been saying for weeks that the race for Senate control will come down to three or four states: Georgia, Nevada and Pennsylvania, with Arizona sometimes thrown in. But is that list too limited?

Political history – and a spat of late spending in the race – suggests that we should widen our focus. Republicans have a real chance at flipping Democratic Sen. Maggie Hassan’s seat in New Hampshire.

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  • The background for the race is simple. Hassan won by 0.1 points in 2016. This year, Democrats spent money during the Republican primary to successfully get their preferred opponent, Don Bolduc, nominated. He has gone back and forth on whether President Joe Biden legitimately won the 2020 election.

    The early polling after the primary indicated that Hassan was a clear favorite to retain her seat. A super PAC aligned with GOP leader Mitch McConnell, went on to pull its advertising out of the race.

    But in the last 10 days, Senate Republicans’ campaign arm started putting money back in.

    What exactly is going on?

    A number of pollsters that don’t meet CNN’s standards for publication have put out results indicating a tight race, or even a Republican advantage. A close affair, though, matches with what the campaigns are seeing in the state.

    New Hampshire is exactly the type of seat you might expect Republicans to be competitive in, given the polling we’ve seen nationally. A CNN/SSRS poll published this week put Republicans ahead by four points on the generic congressional ballot. That’s an 8-point shift toward the Republicans from the final 2020 presidential result.

    An 8-point shift in New Hampshire from the 2020 result would put the seat in play. In 2020, Democrats won the presidential vote by seven points in New Hampshire.

    The competitiveness of the New Hampshire Senate race matches what we’re seeing in other congressional races in New York and New England – about 10 Democratic-held House seats are in play.

    In fact, it would be odd for the New Hampshire Senate race not to be competitive, given all this data.

    Exactly how a Republican win in New Hampshire would affect the Senate map is a bit unclear.

    One view is that New Hampshire would only be won by Republicans if it’s a blowout election across the country. They won’t win it if the election nationwide is close.

    Another view is that the polling averages in Arizona (where most surveys have Democratic Sen. Mark Kelly ahead) and New Hampshire look pretty similar. The states are in different parts of the country and demographically distinct. Sometimes polling errors are concentrated regionally and demographically. It’s plausible that a polling error that affects New Hampshire wouldn’t affect Arizona the same way. And in such a case, Republicans could win New Hampshire while not winning Arizona.

    Either way, New Hampshire could give us an early guide to how the race for the Senate is going. There is not a lot of early or absentee voting in the state, unlike a lot of other Senate seats in play. We should know relatively early on election night what the vote looks like.

    Of course, New Hampshire can march to the beat of its own drum occasionally. Democratic Sen. Jeanne Shaheen retained her seat in 2014, even when Republicans easily flipped the Senate.

    How the Granite State votes this year – compared with the nation as a whole – won’t be known until at least a few days after November 8 and all votes are counted. Republicans, however, welcome the idea that a seat that had looked lost a few months ago is on the radar three days before Election Day.