The first thing is to not give in to fear. "[F]or God gave us a spirit not of fear but of power and love and self-control" (2 Tim. 1:7). Whatever we choose to do should not be driven by fear. Politicians play to voter fears on a number of issues. Fear fuels Americans' acceptance, for example, of the growing security/surveillance state. Participation in the political process through voting or simply expressing a position should flow from rational consideration.
Since voting isn't an option for me in this presidential election, I focus my efforts in other areas. I was pleasantly surprised when the congressman representing my district, a mostly-liberal Democrat (definitely not a "blue dog"), voted to support the Audit the Fed bill. I had emailed this gentleman three different times regarding this bill and got the usual canned responses. But obviously his office received enough pressure on this subject to move him from "unlikely" to supportive. Congressmen do read their mail, and they respond to the winds of their districts. The same applies to Senators, where the Audit the Fed bill faces resistance.
Another piece of legislation that would go a long way toward economic equity would be the Free Competition in Currency Act, on which subcommittee hearings have been held but no action taken. This bill would repeal legal tender laws and allow other media of exchange to compete with the dollar in the market. The pressure on the Federal Reserve to strengthen the value of the dollar would increase its purchasing power and store of value for middle and poorer class savers.
Tip O'Neill famously quipped that "all politics is local," and to some degree the most effective changes are made locally. One issue close to my heart involves the plight of taco trucks (las loncheras) and street vendors. In Charlotte local retail owners have sought help from city hall to restrict these kinds of enterprises. Having worked in the field for many years as a property appraiser I appreciated the taco trucks that moved through residential neighborhoods at lunchtime as I was working. The food is authentic and delicious at a price that can't be beat. While I don't frequent street vendors (I'm not much of a retail shopper) I've read stories of people using this kind of business to put their kids through college. In a difficult economy it is unconscionable for the power of the ordinance to be brought to bear against initiative and an honest living. A Christian concerned with real social justice (as opposed to Jim Wallis-style state-sponsored dependency) can write or speak on behalf of those who stand to be hurt by such restrictions. Let's not forget that Paul used the agora as a place to sell tents and preach the gospel.
I could go on, but ultimately a proclamation of the gospel in any venue includes a witness to what is true, righteous and just. Above all -- and most importantly -- we are called upon to pray for those in authority (1 Tim. 2:1-2) so that "we may lead a peaceful and quiet life, godly and dignified in every way."