I think it is fair to say that most Democrats who run for national office are not fiscal conservatives. Obviously, there is some variability in that some are more fiscally conservative than others. But on balance, few probably deserve to be characterized as the sort of fiscal conservatives a fiscally conservative voter is likely to want. This state of affairs, combined with the Republican Party's embrace of fundamentalist Christianity and vocal opposition to secularism, has always made me feel somewhat sorry for fiscally conservative atheist voters in the U.S. They seem to have few viable options when it comes to casting their votes.
Let's assume that electing fiscally conservative politicians is important to fiscally conservative atheist voters. Aside from some real outliers (e.g., someone like Jim Webb), they will not find many viable options in the Democratic Party. This may lead them to the Republican Party; however, the widespread prevalence of Christian extremists and theocrats in this party probably leaves them feeling like they have few options.
Take Ted Cruz as an example. He might be fiscally conservative enough to appeal to a fiscally conservative atheist voter. And yet, his Christian extremism and obvious disdain for secularism seems like it would be a deal-breaker for many. On the other hand, Donald Trump appears to be a notable exception among Republicans in the sense that he does not seem to be a Christian extremist. On the other hand, his fiscally conservative credentials may not be sufficiently clear to many voters looking for a candidate with a clear record of fiscal conservatism.
It seems to me that it must be quite difficult for fiscally conservative atheists to find political candidates they can enthusiastically support in either of the two large political parties. If you are such a fiscally conservative atheist voter, how do you generally navigate this? Do you end up voting primarily based on economic policy even if it means supporting a candidate who is openly hostile to atheism and/or secularism, settle for less economically conservative policies, or find yourself looking outside the two main political parties for other options?
It seems to me that if religiosity continues to decline in the U.S., we may soon find ourselves with quite a few fiscally conservative atheist voters without a political home. Perhaps the Republican Party will continue what Trump has started and reject Christian extremism. If not, I wonder if we might see a new party begin to emerge at some point.