Final thought: Outside groups can help sway a primary, but the ground needs to be fertile
We've talked a lot about the many millions AIPAC spent to take down Bowman in New York's 16th District and about losing GOP candidates who faced sizable outside opposition from groups that opposed more anti-establishment Republicans in primaries. In many of these cases, these outside groups came in and spent a lot of money to oppose or support a candidate, and, unsurprisingly, that influenced the outcome!
But the candidates also mattered a great deal in making outside groups' lines of attack and support count in these primaries. Bowman wasn't that strong to begin with, for instance, and he'd made headlines for many wrong reasons in recent months. Someone like Williams in Colorado had angered a lot of people in his party, making it easier for the sizable outside investment against him to work. In South Carolina, Burns had Trump's endorsement, but he also had a very controversial background that may have encouraged outside groups to invest in Biggs to beat him.
—Geoffrey Skelley, 538
