Can close when the winner is called by AP, Economist, and other major media outlets.
This removes the individual person risk.
The United States has had 20 presidential elections in the post WW2 era, and in 45% of those the election was won by the same party who had won it 4 years earlier. So the GOP's chance of holding onto the White House is right in line with historical trends.
...which I think those "threat to democracy" people are out to lunch. Nobody would place a 50-50 bet that the CCP would lose control of China by 2028. Nobody would bet even odds that an anti-Putin party will control Russia in 4 years. The fact that this market and Kalshi, are giving GOP a 51% chance of losing in 2028 means the two-party system we've had for 150 years is still firmly in place.
Arbitrage opportunity: https://manifold.markets/TreyMarez/will-a-democrat-win-the-2028-presid-Ry6NpAdLIl