It is likely that Davis will win the election, but the field poll is probably about 25 points too high for Davis. At this point I would say 10 points down for Davis would be fantastic for him. Most observers would put Simon ahead at this point by 5 to 10 points. If Davis is no more than 20 points behind in August he will likely win.
With the money Davis has to spend, he will go very negative on Simon. The attack will not be the usual neagative attack to reduce the base Republican vote. Negative campaigns are usually used to drive down the vote of the other side's base. I think the Davis attack will be to turn the center against Simon. I think the Davis attack ads will run from the middle of September until election day. They will be designed to scare the center and left of center away from Simon. They will likely work. I think the Davis attack on Simon will be much like the Truman attack on Dewey in 1948 or the LBJ attack on Goldwater in 1964.
With California abbout 60/40 Democrat, Davis only needs to win the Democratic base and a bit over 1/3 of the center to win. Simon has to win all his base and better than 2/3 of the center to win. That is next to impossible.
If Davis is successful it may usher in a new way to do negative campaigns. I have always thought it is easier to pry the center away from either side than it is to drive the base awayt.
The base almost always comes home. That is true for both parties. Even when they are very angry, the base comes home. If it looks like their candidate has a good shot atf winning they come home in greater numbers.
Playing to his base is what Al Gore did in 2000. That is likely the reason he lost. Davis will not try to get people to vote for him. He will try to make them afraid to vote for Simon. That usually works.