RINOTom wins the GOP nomination and picks Old School Republican as his running mate. The Democrats go far to the left, nominating Scarlet and running mate JerryArkansas. Being angry that the Republican ticket is not pro-life (even if OSR is pretty centrist on the issue), I launch a third-party campaign and pick Young Conservative as my running mate. However, our ticket makes a conscious decision to only run in the South (the Census definition plus Missouri and minus Delaware, Maryland, and DC) and attempt to throw the election to the Republican-controlled House.
Additionally, election takes place in 2040 (I imagine we'll all be 35 by then), following a period in which Republicans held the White House for 20 of 24 years. Outgoing two-term president Ted Cruz has shrunk the size of the government enough that DC is not as Democratic (due to the government) as it is in real life, and, without such a hefty government presence, it has become more suburban than it is today.
In the election, RINO Tom would have dominated, winning 44 states (losing MA, RI, MD, CA, AZ due to the home-state presence and Phoenix turning into a trendy hipster city in the late 2020s and 2030s, and NM). However, the entrance of a third party in the South splits the Republican vote, allowing Scarlet to win many states. Except, conservatives in the green Deep South states voted overwhelmingly for me instead of RINO Tom. Florida and Arkansas are the closest states, with the vice presidential nominees tilting them from what we would expect (Green AR, Red FL). The conservative House chooses me as president, and the Senate follows by choosing Young Conservative.
