I am not going to search for any studies, but I will be happy to answer this point. If we take as true that poor people and ethnic minorities tend to vote for Democrats, then it is easy to see how voter ID laws dissuade Democratic voters. Had Texas’ voter ID law gained preclearance from the US DoJ, voters would have been required to provide a photo ID such as a Texas driver’s license or state-issued ID or a US passport. To avoid cries of a poll tax, the legislature made provision that the ID would be free for those who claimed to be too poor to pay for it.
Now, let’s take voters in my small, Central Texas town as an example. My town is far from unique. In fact, it is quite typical in this regard. The DPS office that issues ID’s in my town was closed. There is no ID office anywhere in my county. The nearest office is 30 miles away. There is usually only one person working, so the wait is long. (This is not a knock on the person working. She does a great job and manages to friendly and pleasant in spite of it all.) To get an ID, one must present a birth certificate. IRC, a birth certificate from the State of Texas costs ~$20. At $3.50 per gallon, the trip costs $11 in gas and one hour round trip. Let’s say that it takes two hours to complete the transaction (wait time and actually filing the application). At minimum wage, the time invested costs $21.75. So, our “free” ID for voters in my town costs $52.75. With such a steep price, it is easy to see why this disenfranchises voters. This is why Democrats see voter ID laws as a direct assault. It is no coincidence (IMHO) that the ID office in my town closed at the same time that IDs became mandatory.
Voter ID laws are a solution in search of a problem. Their only purpose is to disenfranchise likely Democratic voters. Real, effective election fraud does not take place at the polls. Election fraud takes place when the votes are counted. However, no new laws are out there to address that. I wonder why…