It’s the nation’s most expensive Senate race. Here's where Fetterman’s and Oz’s money comes from.

The fundraising in Pennsylvania’s competitive and hugely expensive Senate race has been a study in contrasts.

Democrat John Fetterman has relied on a steady stream of small-dollar donations: While raising $48.5 million, nearly half has come in increments of $50 or less. Meanwhile, about a quarter of Republican Mehmet Oz’s $13 million raised has come from donations that small. Oz’s fund-raising has been fueled by his own fortune and larger donors pouring money into his campaign.

Oz last week added $1 million more of his own money to his campaign, bringing his personal spending on the race to more than $22 million.