Rich Republicans may have initially balked at Donald Trump, but pro-Trump billionaires are leaving the sidelines in the last week of the election to dump cash directly into crucial counties and swing states.

Hedge fund billionaire Robert Mercer’s Super Pac, Make America Number 1, has suddenly flooded the NBC station in Jefferson County, Florida, with $40,000 worth of pro-Trump ads scheduled to run during football games in the final two days of the campaign. Another group, the Great America Super Pac, run by wealthy diamond importer William Doddridge, bought $187,000 in Trump-supporting ads on the same station in the final week of the race.

The Guardian found the vital donations by cross-referencing election strategy group Axiom’s list of “swing counties” in 10 contested states with local TV stations’ advertising receipts.

Mercer hasn’t always been a major supporter of Trump’s – his Pac originally supported Ted Cruz. But when Mercer came on board, he was a major force, helping to elevate Steve Bannon of conservative website Breitbart within the Trump campaign.

Doddridge, by contrast, has been pro-Trump from the beginning. The last minute ad spend comes as other Republican donors have remained notably quiet. Oil billionaires the Koch brothers, whose financial contributions have underwritten Republican bids for decades, have largely stayed out of the race, spending only to help candidates further down-ballot.

Hillary Clinton’s foothold in Florida appeared to slip in the wake of Trump’s high-volume ad buys, though a renewed push from her the week before the election came to an end that left the candidates neck-and-neck. The most visible Super Pac supporting Clinton is Priorities USA, which is backed by George Soros and Hyatt Hotels co-founder Jay Pritzker, among others.

Another Pac called ISS-America Thrives has appeared seemingly out of nowhere to purchase ad time in bulk in the last days of the election, presumably on behalf of Clinton. The organization spent $12,665 to saturate a single CBS affiliate in hotly contested Sandusky County, Ohio with ads for two days: the Monday before the election, and election day itself.

But despite this last minute splurge, ad spending is likely to be down overall during an election season with two of the most unpopular presidential candidates in history, said Pivotal Research analyst Brian Wieser. “Total year local TV spending in 2012 was $2.6bn, and 2016 probably comes in slightly below this level,” Wieser predicted.

The drop is largely down to the Trump campaign’s decision to rely on free publicity from the media and social media to promote Trump.

During election season, many TV stations, especially in swing states, make the money they will use to fund their operations and equipment upgrades during the following less-political years. Stations add staff, give raises and purchase state-of-the art screens and weather radar for use in the off-season.