Boris Johnson is leading the betting to take over from Theresa May if (when) she steps down. Though he’s not in a great year with a car-crash tr Pluto square his Mars/Saturn now till mid July, returning on and off till late 2018; and tr Saturn opposition his Sun Venus in Dec this year as well. 2018 is worse with tr Pluto opposition his Mars/Uranus on and off all year; and worse a frustratingly stuck tr Pluto opposition his Mars/Pluto in 2018/19; as well as an undermining tr Neptune square Mars/Node in 18/19; and a grind-to-a-halt Solar Arc MC opposition his Saturn (birth time being accurate) in early 2019, followed by major hiccups in 2020. Though by that time he does have one upbeat Jupiter midpoint.
The others I’ll leave till she resigns and they throw their names into the ring.