Wednesday’s Supreme Court ruling against a type of federal campaign-contribution limit would likely affect similar caps in eight states and fewer than a thousand individuals.

The ruling erases one kind of limit, while leaving another intact. The cap that stands in one on how much a donor can contribute to a single federal candidate, party or committee. The cap that was struck was one on aggregate contributions—a cap on the total amount of money spent during an election cycle. The result is that while an individual can only contribute so much to any single political entity — candidate, party or committee — that donor can contribute to as many entities as they see fit.

While 38 states have base limits, just eight have aggregate ones similar to the federal limit struck by Wednesday’s ruling, Chief Justice John Roberts writes on Page 21 of his majority opinionThose states are Connecticut, Maine, Maryland, Massachusetts, New York, Rhode Island, Wisconsin and Wyoming, according to the National Institute on Money in State Politics. (Arizona last year eliminated its aggregate cap.) And those state limits now have a big target on their backs.

Critics of Wednesday’s ruling say it’s basically Citizens United redux, opening the floodgates of spending by wealthy donors. That may be true, but the group likely affected would be small: few donors have hit the federal cap, while even fewer have hit the state limits.

Only 591 donors in the entire country gave the maximum of $46,200 to federal candidates in 2012, according to data from Center for Responsive PoliticsEven fewer individuals hit the cap in the nine states that had aggregate limits in the 2010 and 2012 elections, according to the  National Institute on Money in State Politics.

During the 2012 elections, nine donors in two states gave the maximum amount allowed by state’s aggregate limit,” the authors of an October Institute report wrote. “The 2010 elections saw 159 donors in four states gave the maximum aggregate limit.”

That means the pool of individuals bumping against the cap is well below 1,000, even if there were no overlap among those who hit state limits in 2010 and 2012 and those who hit federal limits in 2012. But spending by those individuals could be influential.

“Though few in number, these donors may be able to have an even larger impact on state elections if these state aggregate limits are lifted,” the authors of the Institute’s October report wrote.

(The graphic below is by Darla Cameron, Dan Keating and Laura Stanton.)