After three straight elections with Republicans trying and failing to turn illegal immigration into a political winner for them, a genuine border crisis means the issue looms larger than ever over President Biden’s 2024 reelection campaign. Polls suggest it’s his worst policy issue, with as many as 7 in 10 Americans disapproving of his handling of it.

But Republicans who have leaned too heavily on this issue have been stung before. And new polling injects some much-needed nuance into how this issue is playing.

Put plainly: This is a significant problem for Biden. But it’s less clear that many potentially decisive voters a) specifically blame his policies or b) see the crisis having an impact on them personally.

The AP-NORC poll echoes others in showing overwhelming disapproval of Biden on this issue. More than two-thirds of Americans disapprove of Biden on both immigration (68 percent) and border security (69 percent). On the former, just 56 percent of Biden’s fellow Democrats and 20 percent of independents approve.

Those are the types of numbers no president wants to see on this or any other issue. And presidents rarely do see such poor numbers, reinforcing how pronounced the problem is.

But the pollster got at the actual impact question in an enlightening way. It asked not just whether people disapproved of Biden, but how much they blamed him and other entities for the situation at the border.

The results:

While 68 percent disapproved of Biden’s handling of immigration, a significantly smaller 48 percent said he’s at least “very responsible” for the situation at the border.That compares to 46 percent who blamed congressional Democrats and the slightly fewer — 41 percent — who blamed congressional Republicans.The percentage of independents who said Biden is very responsible is lower still: 45 percent.The percentage of those who said he’s “extremely” responsible: 33 percent overall, and 32 percent of independents.

The numbers echo a recent Yahoo News/YouGov poll. It showed 57 percent of Americans disapproved of Biden on immigration, but just 40 percent said he bore most of the blame for the situation at the border. Another 22 percent gave him some blame.

It’s not clear how much of this might owe to blame shifting to congressional Republicans after they recently killed a pretty tough border security bill. But polls have shown that Americans strongly supported the bill and that they blame Republicans more than Democrats for that. Biden has made that a feature of his political messaging, including in his State of the Union address. And about as many in the AP-NORC poll gave Congress at least “some” blame — 66 percent — as Biden.

Another key question is how important this issue is to people’s votes. And there, too, the AP-NORC poll provides important context.

The poll shows 62 percent of Americans said immigrants have had a major impact on the country, but a much smaller 29 percent said immigrants have had a major impact on their own communities.

This is something you see often in polling on issues like the economy and crime: believing something is a major problem or issue nationally but not necessarily connecting it to your own lot in life.

It doesn’t mean voters will ignore such things; they might vote on national issues or worry about this broad perceived national problem becoming their own problem. But something is going to be much more of a priority if you believe it’s having an immediate impact on you.

None of which is to Biden is in the clear. But as those recent elections have reinforced, it’s a matter of degree and priorities.

That said, to the extent this is a major, immediate concern for voters, it’s abundantly clear which way it cuts — toward Republicans. And it’s not at all close.

A recent CBS News/YouGov poll asked what people thought would happen with border-crossers if either Biden or Donald Trump won. Americans said 50 percent to 22 percent that they expected border crossings to increase rather than decrease of Biden won. If Trump won? That more than flipped, with Americans saying 72 percent to 9 percent that border crossings would decrease.

In other words, expect Republicans to spend the next seven months trying to make sure people care about — and fear — this issue. Again. Whether they’ll succeed is the big question.