NPR interviews DNC chair Ken Martin after Democrats won the Senate, House, key governorships and state legislatures in the 2026 midterms, flipping Republican-held seats in conservative states. Martin calls it the party's best result in a century, says voters gave Democrats a mandate on affordability, health care and a "corrupt system," and notes the party now has "great leverage," though how promises become policy remains open with President Trump holding veto power.