“Basically, Trump has now been committed to the equivalent of land war in Asia by having to spend so much of his money in Florida, a state he has to win to get to 270 Electoral College votes,” Schale said. “And as a result, he doesn’t have the resources to compete everywhere he would like.”

Schale said his group and the other major Democratic super PAC, Priorities USA, have been able to focus their dollars in other parts of the country, particularly the Upper Midwest. Democratic super PACs, meanwhile, have been able to focus more attention on Arizona, North Carolina and Georgia — once-reliably red states where the president has also had to commit additional resources for the past month, in addition to Florida.

Florida, the largest and most-expensive swing state, has 10 media markets and is so competitive that outside groups and the presidential campaigns have spent and reserved a record $263 million on TV ads from June through Election Day, according to data compiled by the media tracking firm Advertising Analytics.

Since the beginning of September, Trump has added more than $6 million to his total in ad spending in Florida, according to Advertising Analytics. During that same period of time, with Democrats freed up to attack elsewhere, the Trump campaign has also been forced to plow more than $7 million in ad spending into Georgia — a state he was once expected to win easily — and nearly $6 million in Arizona, another state he won in 2016.

Trump also decreased planned spending by nearly $13 million in Ohio, more than $6 million in Minnesota and nearly $3 million in Wisconsin, reducing his advertising footprint in the region.

David Johnson, former Florida GOP executive director, said the Bloomberg money has had a clear effect on forcing Trump to withdraw to his core states, instead of competing across a wider national map.

“This is not your 2016 election, so abso-freaking-lutley the Trump team knows they have to maintain something closer to parity in [gross rating] points and spots in the home stretch,” Johnson said. “You best not be massively outspent in Florida the last two weeks and expect to perform well on Election Day, where Republicans have to turnout in vastly larger numbers to win.”

In Pennsylvania, former Republican Congressman Phil English said Trump’s campaign has a clear advantage on the ground, where the GOP spent all summer organizing and knocking on doors. But on TV, English said, there’s a huge disparity in the area he once represented, Erie County, one of the bellwethers of the swing state.

“The Democrats are literally flooding everything with anti-Trump and pro-Biden advertising. It’s a concern,” English said. “We’re definitely seeing seniors reacting to the coronavirus here, and the steady messaging from Democrats over how the Trump administration has handled coronavirus has moved a lot of people.”

Trump’s advisers say they are confident about the amount of money they have to spend on TV across the map — announcing a $55 million ad buy this week — and outside groups are backfilling for Trump in some states where he has drawn down his own spending.

The pro-Trump super PAC America First Action, for example, has added nearly $17 million in ad spending in Pennsylvania and more than $5 million in Wisconsin since the beginning of September, according to Advertising Analytics. It has added nearly $8.8 million in Florida.

Even so, Biden’s financial advantage in the home stretch — and Trump’s vulnerability in once-safe states — has unexpectedly forced the former vice president to make difficult decisions about where to spend it all.

“The contraction of the Upper Midwest and the failure to keep TV advertising there speaks to [Trump’s] flagging possibilities to win,” said Doug Herman, who was a lead mail strategist for Barack Obama's 2008 and 2012 campaigns.

Fernand Amandi, a veteran Democratic pollster and consultant in Florida, said “In the closing days of a campaign, follow the money means follow the problems. Clearly there is concern in the Trump camp as they vote with their wallets to try and restore states that, if they’re in jeopardy, spell real problems for their campaign.”

Trump’s Florida squeeze isn’t all Bloomberg‘s doing. At the same time the former New York City mayor was ramping up his Florida spending, Trump’s campaign was experiencing a cash crunch from too much spending and too little funding. But Bloomberg’s money, by design, has added to the pressure on the president

“It’s virtually impossible for Trump to win the presidency without Florida, and that is why Mike Bloomberg is investing $100 million into the race there — to turn it into a state Trump and Republicans have to work hard to win, and to free up Democratic resources to other states like Pennsylvania that can solidify a Biden victory,” said Kevin Sheekey, Bloomberg’s senior political adviser. “Florida is a key state for winning the presidency — and where we hope Donald Trump makes his residency permanent after he loses.”

Max Steele, a former Florida Democratic Party spokesman and current senior communications advisor with the liberal group American Bridge, said his organization has noticed Trump’s scaling back in Michigan, Pennsylvania and Wisconsin. That’s where American Bridge has been focusing on getting Obama-Trump voters to flip back to the Democratic fold.

“That’s the point of Bloomberg’s spending: keep him mired down. Florida is a money pit,” Steele said.

One thing remains unclear about Bloomberg’s TV ad spending — the efficacy, compared to social media or news coverage of the final two weeks of the campaign. Both sides recognize it’s taking place against the backdrop of a highly polarized electorate in which few voters remain undecided.

“I think one of the things we’re going to find this year is that there has been a much higher percentage spent on social media and voter contact,” said Saul Anuzis, a former chairman of the Michigan Republican Party. “I think this is a base election, not a swing selection, so you’re having a much larger percentage of money spent on get-out-the-vote and communicating with your supporters.”

Samantha Zager, a Trump campaign spokesperson, pointed to the Trump’s campaign’s ground game, his digital spending and his data operation as advantages over Biden that counteract Democrats’ TV spending.

“Considering President Trump won in 2016 and the DC establishment got itself worked up over the exact same issue then, maybe it’s time for the mainstream media to accept our winning strategy and start questioning why Joe Biden is needlessly overspending on TV.”