You can run physical mask to cover up the obvious effects of possession. Astrally, it'll still be obvious, but to mundane and technological sensors and drones (if you can roll well enough) you could pass for normal.
You'd need some means of sustaining it, however.
With regards to Con 1 + spec + mentor spirit = incumbent politician: LOL, no.
The developers never bother to give us full dicepools, only totally useless information about skill ranks - which are often a relatively insignificant component of an efficiently constructed dicepool. So we have no idea what the total dicepool of an incumbant politician is after we account for adapt abilities, or 'ware, or specializations, or empathy software, or buff spells, or positive qualities (or hell, even negative qualities). But you can probably bet that their dicepool would be a multiple of your 8 die con pool.
The Dice Pool of a politician wasn't really the point though, the point was she has a higher dice pool than anyone you've ever met :p
I've upped it to 10 in the latest draft though, should help a bit at least.
edit: Ok, changelog:
-Switched 1 Agi to Rea
-Removed some superfluous skills and skill groups, now have spellcasting 4, counterspelling 4, summoning 4 and binding 4, with a specialisation on all but the counterspelling. Also dropped the 1 in astral combat.
-Sustaining focus from 4 to 5.
-Switched out some spells for others.
-Now Fashionably reach 10/10 in armour.
-Got some Nuyen and BP to spare for contacts/random stuff ^^
Thanks for helping me make the character 20% cooler, guys!
