Any form of bigotry contains within it a combination of the overt and the subtle (which has been dubbed "stealth" by those who like to play games with words). Racism and sexism have very different expressions, in both the relative amount of each type and the permeation within the United States.
Overt bigotry is fairly straightforward. It is fear, ignorance and loathing. Integration and education do a good job of getting society past this, but it takes time (like generations). The overt bigot will never vote for any member of a group they are bigoted against. This type of bigotry has diminished quite a bit over the past 60 years. It still exists (particularly in certain areas of the country), and it is far more common with respect to racism--or really toward outside/other groups: Hispanics, Muslims, blacks, LGBT--than sexism.
The subtle bigotry is more prevalent for all types. It is harder to identify the causes, but the general solution is the same, though the level at which it must be applied causes serious problems (just try to force integrate a fortune 500 company or a major university...or a legislature). Moreover, there is no consistent way to identify it. People who are bigoted in this manner may actually vote for a member of a certain group as a way to "demonstrate" how not-bigoted he/she is. People who oppose affirmative action may be more likely to be bigoted but it is hardly a given. As such it is very difficult to discern the effect of this type of bigotry on something like an election. It is real; it does have an overall negative effect on the group that it targets, and there may never be an effective measure to demonstrate it (yes, this includes salary disparity).
I would argue that, though it is confined almost exclusively to the latter category above, sexism is far more pervasive overall. There are myriad reasons which have been given, but there is an underlying one that is as often discarded as it is brought up, but provides the only real differences between men and women which lead to all subsequent treatments of either by either. That is that there are biological differences between men and women. These differences go well beyond: one has a penis and the other a vagina. Hormone levels, gland function and neural activity all vary. Behavior and thought processes have differences based in physiology and biochemistry. One cannot truly understand the other (understanding even this is actually a pretty big step). It is, I would argue, these differences which lead to differences in psychology that allow for the basis for what de Beauvoir writes on in Second Sex (read it, I'm not summarizing here).
I should stress that this in no way implies that one is better or even preferred in any given situation. To the contrary it would imply that an idealized world would have roughly equal numbers of men and women at all levels and functions so as to provide the best balance in opinion, thought and productivity.
In the end bigotry in all forms, including racism and sexism, still exists, but it is most often difficult to spot. Moreover, while the effects are mostly negative they are also not something so easy to discern, particularly in, say, an election.
***note: Sexism is unique among the various forms of bigotry. I've said before (I think here somewhere) that I am a fan of Simone de Beauvoir's writing on the issue of sexism, so some of what I feel on that issue can likely be traced back to Second Sex; I use her writing as a guide. I believe that she did well to describe the sociology that I see as the result of our differing physiology/biochemistry.