That's because the former New York mayor's presidential campaign has poured more than $170 million into TV and radio advertising in the first Super Tuesday states -- more than 10 times that of any of his Democratic rivals.
With so many states holding primaries on Tuesday, spanning the country from Maine to California, where does a less well-funded campaign put their money into media advertising? Do you try to show ads in California and Texas, two of the most expensive media markets in the country? Or make up for lost ground in states with cheaper ad rates? Is it better to spend a large amount on a few states, or a little in every state?
For example, Pete Buttigieg, before ending his campaign on Sunday, decided to cover as many states as possible (12), even if the ad buys were smaller than his competitors.
Amy Klobuchar, on the other hand, spread $4.6 million over eight states. More than half of that money, $2.49 million, went toward ads in North Carolina and Virginia, while states favoring the more liberal Bernie Sanders in the polls were left alone. A campaign aide said Klobuchar would end her campaign on Monday, a day before Super Tuesday.
As seen in the chart below, the spending numbers collected by Kantar Media/CMAG help illuminate the strategy of the five Democratic candidates left in the race.
Michael Bloomberg not only paid for ads in every state -- he leads in spending for every state by wide margins.
Bernie Sanders spent more than $16 million on ads in nearly every Super Tuesday state, including $7 million in California. What state did Bernie leave out? His home state of Vermont. Only one candidate still in the race paid for ads in Vermont: Bloomberg.
Elizabeth Warren has only spent about $2 million on ads going out to seven states. However, with an $11.7 million assist from her super PAC -- Persist PAC -- she was able to cover six more states for a total of 13.
Joe Biden, coming off his win in South Carolina, has only paid for about $1.5 million in ads in eight states. All of those states aside from California are in the South, where he enjoys a polling advantage.
Tulsi Gabbard has spent $148,195 in just three states, but two of them are big markets: California and Texas.
One question that remains is how much ad spending carries over to the ballot box. Businessman Tom Steyer, who ended his campaign over the weekend, spent a total of $22.5 million on media ads in South Carolina. Not only did Steyer place third there, but he failed to garner enough votes to qualify for delegates.