Republican candidates will begin squaring off Monday in Iowa as caucusgoers and voters start deciding which GOP nominee will take on President Biden this November. 

The Republican primary race has been underway for almost a year and has included large-scale attacks as candidates have jockeyed to close the gap between themselves and former President Trump, who has maintained commanding leads in polls.

But despite Trump’s frontrunner status, he has not been the most targeted GOP candidate. Instead, the candidates battling behind him have set their sights on each other, attempting to cut down and distance themselves from their challengers.

The race has featured extensive cash poured into political maneuvering, including attack ads. Florida Gov. Ron DeSantis has been the most targeted GOP candidate in that regard as voters begin selecting the Republican presidential nominee.

According to Federal Election Commission filings, DeSantis has faced nearly $48 million in negative independent expenditures, including TV and radio ads. Former South Carolina Gov. Nikki Haley has been attacked the second most, with almost $24 million in negative independent expenditures going toward her.

Haley and DeSantis, in particular, have targeted each other relentlessly as they attempt to solidify themselves as the Trump alternative.

Trump, meanwhile, has faced $23 million in negative independent expenditures, filings show. President Biden has seen $21 million in such spending aimed at him.

Iowans will head to more than 1,600 caucus sites Monday night while braving frigid below-zero temperatures to cast ballots in the lead-off contest of the 2024 Republican presidential nomination race.