It could depend on the state. In California, I have not seen any signs for either Trump or Clinton, and the commercials I have seen are ones that were sold nationally; I am assuming that both sides are conceding California to Clinton and are saving their money for the battleground states. Since both candidates for Senate are Democrats, and very few House races are in doubt, I don’t see signs or commercials for those either.
The signs I do see (a) tend to be at intersections rather than on front lawns, and (b) stick to local races. As for bumper stickers, I have two theories: one, I don’t think they’re free any more, and two, people may be afraid that they won’t be able to get them off entirely, and it will bring the value of the car down.
I’ve had my car vandalized when the only stickers on it were a Black Flag sticker, and one that said “Listen to Black Sabbath”. People get irate at random things sometimes.
I am in southern California working for a tech company in area area with a lot telecom and bio tech companies. 4 years ago there were a fair amount of Romney and a lot of Obama bumper stickers and yard signs. This cycle there are no Trump signs at all and every once in a while I see a Trump bumper sticker. I see way more Romney stickers from last cycle than Trump stickers now. There are quite a few Hillary stickers but definitely down from Obama.
Zeppelin fans – what can you do? They’re hellbent on erasing the truth from the history books, that Sabbath invented metal.
But don’t you dare mention Ray Davies to a Sabbath fan… 
I’ve never seen the point of political bumper stickers. Even with the interminable length of the election process, eventually there will be a point where either you’re driving around with a bumper sticker for an election long over or you have to go through the effort of scraping it off.