Of the four alternatives listed, the best value is in my opinion, the 20/1 on offer about the 53-year-old Senator for New York, Kirsten Gillibrand. The 40/1 available about her winning the keys to the White House is even better. Win or lose, they look to be great value bets to kick off the political year. 

Kirsten Gillibrand to be the next Democrat Nominee for US President - 1pt @ 20/1
Kirsten Gillibrand to win the next US presidential election - 1pt @ 40/1