In a democratic system, there is less risk than otherwise of citizens being left behind in poverty. There are two reasons.
First, your country is more likely to be prosperous, and with more prosperity there is likely to be less poverty.
Second, it is more likely that there are antipoverty policies in place. The reason for that is that even the poor have a share of power in the vote. Competing political parties or élites need the votes of the poor, as they need other votes, and must therefore to some degree satisfy the interests and demands of the poor and those in risk of poverty. If you have the vote, someone in government is likely to take an interest in you. If you do not have the vote, it is unlikely that anyone in government will speak for you. If you have the right to stand up for your interests, you are less in risk of your interests being disregarded.
One of the great movements in the twentieth century was the emergence of mature welfare states in most democratic countries. That followed on from democratisation in the first half of the century, with the extension of the vote first to all men and then to women. There is a causal link from political democratisation to the inclusive welfare states. To be sure, democratisation is not the full explanation. Other factors include economic crisis and precariousness, demographic fluctuations, the experience of the Second World War, and post-industrial economic restructuring. But democratisation is an essential contributing part of the explanation.