It probably wouldn't -- My state is one of those that do require an ID and I haven't read of any issues of voters not voting because of it. Heck, we just tossed out a repug gov.
Remember, these are political geniuses at work and therefore doesn't need to based on any type of reality. Besides -- do you really think republicans can win in 2008 on the ideas they've represented over the past several years? They have to pull every trick they can to suppress the votes of people they know won't vote for them. How else will they win

btw -- did you hear about the trick they tried to pull in California recently? They tried to get enough signatures to get a referendum onto the ballot to allow their electoral college votes to be split based on who won each district instead of winner take all, effectively giving republicans an extra 20 electoral votes. They had difficulty in getting enough signatures so they placed the referendum on a clipboard under another petition about children's cancer or something like that and asked the people to sign multiple times and didn't tell them what was under the top petition.
This is the modern day gop at work!
(p.s. the referendum failed to get enough signatures)