On the eve of Iowa’s presidential caucuses and the start of the 2024 primary season, what’s the inevitability of a Biden-Trump rematch? David Brady and Douglas Rivers, Hoover Institution senior fellows and Stanford University political scientists, discuss various political dynamics heading into Iowa and beyond including whether there’s room for three viable Republican candidates in January’s and February’s contests, the number of persuadable voters in a polarized “two-incumbent” general election, the role of third-party candidates as mischief-makers, plus alternate ways for selecting presidential nominees – i.e., is it time for national, regional or more “open” primaries?