Caging is a term used to describe describe quasi-legal or illegal suppression of the vote. It is seen as a weapon which one party uses against another. Actually both parties engage in 'caging' to suppress voters who dissent from the entrenched party duopoly.
Gerrymandering is the most time worn example of caging using 'cracking' and 'packing' to divide the political market between two parties. One thing about such tactics is they become less effective as the number of candidates outside of the duopoly increases. Therefore, alternative party candidates must be suppressed by other techniques such as ballot access restrictions and filing fees to keep the two-parties entrenched.
What is less appreciated is the is the role gerrymandering still has upon new party candidates even when ballot access barriers are drastically lowered. Parties based on appeals that cut across ethnic, socio-economic characteristics have a geographically dispersed constituency. Their constituencies are still 'cracked' or fragmented by geographical divisions. The entrenched parties remain entrenched even with ballot access reforms. This factor controls even if ballot access restrictions are totally removed. In those cases, the minority parties are disparaged as 'spoilers' because they reveal the illusion of 'majority rule'.
However, if geographical boundaries are retained solely for the purpose of counting votes the 'majority rule' convention can be reasserted buy counting individual's votes within a larger context which is closer to proportionality. The solution within the constitutional framework of the U.S. is to allow individuals to swap electoral districts to overcome 'cracking'. This allows voters to voluntarily 'pack' a district and break the hegemony of the entrenched parties to 'crack' them into permanent minority status.
Ten thousand voters in a state who, but for cracking, could control an electoral sub-district are emancipated into a represented group. This consequence alters the 'viability' of new candidates.
So ballot access reform is a necessary, but not sufficient reform to secure a wider base for representation. But even both of these reforms are not sufficient either.
The total population size of the representational district remains to dilute and eliminate new political constituencies. I address this problem as well.
But if when ballot access is open, voters are free to cross electoral boundaries, and electoral districts are reduced in size (more representatives), the voter still confronts a fundamental paradox. The voter must make a 'take it or leave it' choice for only one candidate. The voter cannot express a range of preferences among multiple candidates. This problem is addressed by 'range voting'.
Finally, the problem of how to finance candidates without bribery and extortion remains. Since 1973 I have argued that mandatory anonymous contributions are an essential companion to the anonymous "secret' ballot. This is now technologically feasible and essential to a comprehensive attack on the system of entrenchment which has given Americans such deep cynicism which has allowed the virtual destruction of constitutional civil liberties by the entrenched parties coalition.
The American electoral system is killing democracy and the death of democracy is killing the Republic. Electoral reform is essential to a constitutional restoration. If this fails nothing remains but dictatorship and revolution - a bloody madness that could far exceed the excesses of the French Revolution or even the first American Civil War. Sounds hyperbolic? There is no need to find out. Just take the reform path step by relentless step.