A brand new WMUR Granite State poll shows New Hampshire’s US Senate race tightening considerably:

A new poll shows that a possible race between U.S. Sen. Jeanne Shaheen, D-N.H., and Republican Scott Brown is a tossup. Last month, Brown trailed Shaheen in the WMUR Granite State Poll by 12 points. The new poll shows Shaheen leading brown by 2 points, 46 percent to 44 percent. “I feel very good because when I’m going out and about into people’s businesses, holding town halls — town halls are an important thing — and conveying my thoughts about being an independent voice for New Hampshire, it’s resonating,” Brown said…Shaheen could be getting dragged down by President Barack Obama’s approval numbers, which sit at an all-time low in New Hampshire.

The Brown/Shaheen head-to-head hasn’t been even remotely this close since, well, we wrote about this Dartmouth survey back in early May.  Since then, the race has appeared to be slowly slipping away, with the incumbent leading by roughly 10 points in most polls.  We’ll see if the new WMUR poll — which is very respected in the state — is a blip, or the first data point in a trend.  Since the outfit’s last poll showed Shaheen’s leading challenger down by a dozen points, Republicans have been consoling themselves with this history lesson from the station’s political director:

The reality is that this race, like Shaheen other races for Senate in 2002 and 2008, will break one way or the another [much] later in the fall, possibly even in the last two weeks. History should tell us something. In 2002 Shaheen was leading her Republican opponent going into the last week and then lost. In 2008, the race broke Shaheen’s way in the last month.

But these new numbers can’t be construed as a ‘late break.’  What might explain the ten-point swing in the course of one month?  Part of it may be the fact that Brown has been holding one public town hall meeting after another, while Shaheen has refused to conduct any.  (Does that dynamic — Brown criss-crossing a state, out-hustling an entitled and cloistered Democratic opponent — stir any memories?)  Brown’s campaign has also been relentlessly hammering away at Obamacare, which is highly unpopular in New Hampshire, and for good reason. But Obamacare’s been a thorn in Shaheen’s side for months, during her highs and lows, and the cumulative effect of intensive retail politics doesn’t generally amount to a double-digit swing in such a short time span. So what else could be driving the big shift?  Take a look at Brown’s last two television commercials:

He’s been hammering on immigration for weeks now; the first spot posted above pre-dated Tom Cotton’s tough ad in Arkansas. Meanwhile, Terri Lynn Land is also running an immigration-themed ad up in Michigan.  Someone, somewhere obviously believes the resonance of the border crisis as an issue isn’t limited to red states.  To wit, when an in-depth polling memo from the NRSC landed in my inbox yesterday morning (hours before the WMUR poll was released), I was a bit surprised to see Shaheen featured as one of the incumbents listed as “primed for defeat.”  The polling picture linked had been pretty ugly for months, I thought.  Do they know something we don’t, or is this just pro forma partisan rah-rahism?  Regardless of whether the NRSC was tipped off on the survey that was about to drop, one element of their analysis jumped off the page:

Internal polls show that her opposition to increased border security and her role in Obama’s push for “Executive Amnesty” are extremely potent in the Granite State.

Internal polls driving a “potent” on-air message may have revived Brown’s campaign, at least for now.  I’ll leave you with two questions: If this momentum is real, can Brown keep it rolling over the next two-plus months?  And do you think Shaheen might be among those leading this frantic, behind-the-scenes charge?

Context: Sargent often serves as a DSCC stenographer, and Shaheen has been known to cast about for quick, short-term fixes to her self-inflicted political problems.  Obama’s rumored executive amnesty may have to wait.