I'm a democrat, and support the idea that people should provide ID in order to vote; this is a reasonable and important step to prevent voter fraud.
In today's world, there is no legitimate excuse to not have a valid Photo ID. You shouldn't even be able to cash a check, write a check card, use credit card, unless you can prove who you are.
Even if you loose your drivers license, as a result of a DUI, or if you never had a drivers license, or whatever; you can still get a state issued non-driver ID. They are cheap, probably cheaper than a 6-pk of beer, and you can usually get them on the same day you apply for one.
Some people may hesitate to get a photo ID. Certain criminals, for instance, drug dealers, often destroy their ID's, and adopt an alias. Those people want to avoid being identifies. Anyone with an active arrest warrant, might also be afraid to apply for an ID. Those who owe money to the child support police, might be afraid to get an ID.
The only valid reason I can think of for not having the ability to get an ID, is if you are homeless, and are unable to prove your residency. In cases like this, there are homeless shelters, social service professionals, and advocates who can assist homeless individuals. Voting is usually the least of their worries. Only a very small percentage of Americans will even have this problem, and even a smaller fraction would even want to vote. For those who do want to vote, there are people out there advocating for them so they are able to do so.
Other than that, I don't buy the argument that it's unreasonable to require personal identification in order to vote. Without ID, minors could try to vote, people could try to vote multiple times at different precinct locations. People have even tried to vote on behalf of people who are already deceased! Therefore, as a democrat, I'm 100% in favor of the ID requirement. I would assume that all Americans who want to see fair and accurate elections would be in favor of it also.