We may see a new battleground map in the Electoral College, if new NBC/Marist polls give an accurate picture — and that’s not good news for Republicans. States like New Hampshire and Nevada have been hotly contested in the last several cycles, but Arizona and Georgia had remained safe Republican territory. Not so in these polls, and trends in other polling tend to corroborate them:

With a combined 37 electoral votes hanging in the balance in Arizona, Georgia, Nevada, and New Hampshire, Democrats Hillary Clinton and Tim Kaine and Republicans Donald Trump and Mike Pence are highly competitive among likely voters in each state including voters who are undecided yet leaning toward a candidate.  This is in contrast with 2012 when Republican nominee Mitt Romney secured both Arizona’s and Georgia’s electoral votes, and President Barack Obama carried Nevada and New Hampshire in both of his victories for the White House.  In 2012, each candidate carried their respective states by wider margins than Clinton and Trump are currently able to achieve. …

In both two-way and multi-candidate matchups, likely voters move the presidential contest more Republican except in New Hampshire.  This is primarily due to the increase in the proportion of white voters within the likely electorates of Arizona, Nevada, and Georgia.  This is accompanied by the decline of Latino voters in the likely electorates of Arizona and Nevada and minority voters, overall, in Georgia.

To put this in context, Mitt Romney won Arizona 54/44 and Georgia 53/46 over Barack Obama’s superior organization four years ago. RCP averages show similar results, too, with Trump’s lead in Arizona down to less than two points, and exactly two points in Georgia. Hillary’s up by less than a point in Nevada. Only the aggregate average in New Hampshire has Marist off the mark, with a six-point Hillary lead.

The Marist polls don’t deliver bad news in the narrow context of these questions; Trump remains slightly ahead in Arizona and Georgia, and in range in the other two states. One can also argue that Hillary has a similar problem in that she falls below the Obama metric in states he won 52/46 in 2012, and by wider margins in 2008. The problem is that Hillary can win without New Hampshire and Nevada, thanks to a built-in Democratic advantage in the Electoral College, while Republicans cannot afford to lose a single state they won in 2012.

Even a swap does little good; Arizona and Georgia combine for 27 electoral votes, while Nevada and New Hampshire combine for only ten. That would leave Republicans looking to make up 17 electoral votes just to keep pace with a losing 2012 effort, making a Pennsylvania pickup all but meaningless.

In other words, this isn’t exactly great news for the GOP. However, the data from Marist about the Senate races in three of these states looks a lot sunnier:

Marist #s brutal for Ds.
McCain 57, K'patrick 38
Heck 47, CCM 45
Ayotte 52, Hassan 44
If accurate, Rs hold Senate.https://t.co/zrnKQLuswL

— Paul Kane (@pkcapitol) September 12, 2016

The RCP averages more or less match these results too, but the New Hampshire outcome departs significantly from the 0.5-point Hassan lead before Marist published this poll. All three of these polls show a dynamic that has played out over the last several months in state after state. Donald Trump’s presence at the top of the ticket does not appear to have much impact farther down the ballot, and Hillary Clinton’s presence and media advantages aren’t helping Democrats. If those trends hold — and Republicans are certainly organizing to make sure they do — then Democrats may lose a once-a-decade opportunity to seize control of the upper chamber.