They became more candidate centered. They were much less enduring as real subjects out there in government. And where they let fusion back in, third parties reappeared. The states didn't want fusion to happen because the states themselves are creatures of the major parties. Rory Millson, counsel for the Conservative Party of New York, agrees.
Third parties threaten that.
Sarah Siskind, a lawyer for the New Party, pointed to Minnesota's new fusion legislation as an example of party reluctance to allow fusion. The state now has to create laws that allow for fusion. Minnesota chose to do the latter. The state legislature made it difficult for minor parties to sustain themselves even with fusion. It passed a bill that requires a ballot with the fusion candidate's name only on the major party line, with the minor party's name merely listed next to the major party's name.