There’s good news and bad news for proponents of legalizing marijuana.

The bad news: New polls show it’s a losing fight in three states — by a slim margin in Pennsylvania and sizable margins in Iowa and North Carolina. The good news? It’s doing far better among the youngest residents of each state.

That’s according to new polls out Monday from Quinnipiac University (Pennsylvania), the Des Moines Register (Iowa) and Elon University (North Carolina). All the polls underscore an important point in the state-level debate over marijuana policy: Even though there are significant party differences, opposition is only as strong as the state’s oldest residents. It’s hard to predict how the balance of power between parties will shift. But age only moves in one direction. As long as those attitudes don’t change drastically, the legalization effort can look forward to a wave support.

Take North Carolina. Most people oppose the idea of legalizing pot, with 51 percent saying they don’t believe marijuana should be legal and 39 percent in favor. Opposition also beats support in both parties, though Republicans are way, way more opposed than Democrats.

But when it comes to age, support increases the younger you go. Among seniors ages 65 and older, 63 percent oppose legalization while 25 percent support it. The opposite is true among North Carolinians between 18 and 30 years old: Legalization enjoys 54 percent support while 39 percent oppose the idea.

In Iowa, opposition wins out among all demographics, even the young. About one in three Democrats and independents support legalization, but only about one in six Republicans do. The age gap is significant though, according to the Des Moines Register.

“Just 47 percent of Iowans 65 or older support legalizing medical marijuana, compared with 67 percent of those younger than 35,” the paper reported. “The split is even more dramatic on the question of legalizing recreational marijuana. Only 13 percent of Iowa seniors support that idea, but 39 percent of young adults do.”

The prospects for legalization are probably best in Pennsylvania, where there’s a nearly even split generally. Some 49 percent oppose legalization, just a single percentage point more than those who support it. Support is greatest among Democrats, followed by independents, and Republicans strongly oppose it. Legalizing weed enjoys only 29 percent support among seniors, with 66 percent opposing it. But it’s nearly the opposite among the youngest demographic. Among Pennsylvanians ages 18 to 29, 64 percent say possession of the drug should be legal in small amounts while only 34 percent say it shouldn’t.

The striking age gap isn’t limited to just those states with new polls out Monday. A Quinnipiac poll last week showed that while Ohioans support legal marijuana by 51 percent to 44 percent, the margin is largest by far among the youngest demographic. For that group, 72 percent support legalization with 25 percent opposing it. Among seniors, 65 percent oppose. The generational gap exists nationally, too.

Proponents of legalization have a wave of support to look forward to, as long as they can harvest and maintain positivity among the youngest voters.