Trump is losing a must-win state

Barack Obama lost the state in 2012 by 2 points in 2012, as he won nationally by 4 points. In fact, the only Democrat to carry North Carolina in the past 40 years was Obama in 2008. It was a narrow 0.3-point win.

If Biden's current polling edge in North Carolina were to be the final result, it would be the best Democratic performance since southerner Jimmy Carter won the state by 11 points in 1976.

No Republican has won the presidency without North Carolina since Dwight Eisenhower did it in 1956.

Put another way, Biden does not need to capture North Carolina to take the presidency. Winning the state would be gravy for him. As I noted earlier Sunday, Biden's best path to the presidency likely runs through the Great Lakes battleground states.

Trump, however, doesn't have that luxury. Biden is currently posting considerably larger leads than he is North Carolina in every state Hillary Clinton carried in 2016, as well as Florida, Michigan, Pennsylvania and Wisconsin. He's probably doing better in Arizona as well. Those states combined, without North Carolina, get Biden to about 320 electoral votes.

If Trump is losing in North Carolina, he's almost certainly losing in enough states to fall short of an electoral college majority.

Indeed, North Carolina is reflective of the electoral college map story right now. Biden is winning in states he needs to win. Trump, though, is in trouble in a number of states he must carry.

Just this morning, another CBS News/YouGov poll put Biden and Trump within the margin of error (46% to 45%) in Georgia among likely voters. That comes on top of a Monmouth University poll that had the two tied 47% to 47% among registered voters. Georgia hasn't gone Democratic in a presidential election since 1992.

But while North Carolina may not be necessary for Biden to win the White House, it is a key piece in the Democrats' efforts to take back the Senate. Remember, they need a net gain of three seats (if Biden holds onto his lead over Trump, as his vice president would become the tie-breaking vote) or four seats (if Trump comes back to win).

Democrats have long held a lead in Republican held seats in Arizona, Colorado and Maine, while trailing in Democratic held Alabama. A win in North Carolina would likely put them on the road to a net gain of three seats.

The CBS News/YouGov poll gives Democrat Cal Cunningham a 48% to 39% lead over Republican Sen. Thom Tillis. The NBC News/Marist College poll last week had Cunningham up 9 points as well.

Cunningham's expanding lead is a prime example of how the Democratic position has improved greatly since the early spring. Back then, Cunningham and Tillis were basically even in the polls. As in the fight for the Senate, Democrats' chances of winning in North Carolina have gone up since that point.

I should point out that the North Carolina polling did underestimate Trump and Republican Sen. Richard Burr in 2016. Importantly, however, Biden and Cunningham are ahead, while the Democratic candidates for president and Senate were trailing at the end of the 2016 campaign. In fact, Cunningham is doing better than Democratic Senate candidate Deborah Ross was ever doing in the 2016 race.

It's just a fact that Democrats are in a better position than they were in 2016. If Republicans want to win this year, they can't pin their hopes to a polling error. They simply must do better.

Otherwise, Trump won't just lose the presidency. He'll take down the Republicans' Senate majority with him.