CNN’s poll of registered voters nationwide show Joe Biden leading Donald Trump 51 to 46 percent. But it’s a different story in the battleground states, where the race for president will be decided. (emphasis is mine)

Though other recent polling has shown some signs of concern for Biden among younger voters and strength among older ones, few have pegged the race as this close among younger voters. The results suggest that younger voters in the battleground states are tilted in favor of Trump, a stark change from the last CNN poll in which battleground voters were analyzed in March, even as other demographic groups shifted to a smaller degree. Given the small sample size in that subset of voters, it is difficult to determine with certainty whether the movement is significant or a fluke of random sampling.

If this is a trend and not a fluke of sample size, the Biden camp will be worried. The question for the president is this: How will he, on one hand, tell older people not to worry about cuts in growth to entitlement programs such as Medicare, while on the other hand, defend astronomical spending and debt that younger voters must shoulder? The results put even more pressure on Mr. Biden to up his game and to choose a vice presidential candidate that bridges a generational divide.