why do third parties have limited success?

1) the electoral college, and the FPTP 'winner takes all' system; this means that if a third party does not win a majority within the popular vote of the state, the third party will not receive and electoral college votes. as a result, they fail to have significant influence as they would need to be bigger than the 2 main parties within the US. this is something incredibly hard as the US has always been a 2 party democracy. 

2) third parties lack the criteria to receive matching funds as they…