This just came across the transom in electionline:
Same Day Voter Registration in Maryland – R. Michael Alvarez, California Institute of Technology; Jonathan Nagler, New York University, Demos, Briefing Paper, Winter 2010: In analyzing the potential impact if Maryland adopted same-day registration, the authors find that overall turnout could go up by 4.3 percent, turnout among those aged 18 to 25 could increase by 9.1 percent and turnout for those who have moved in the last six months could increase by 7.2 percent.
It’s a nice piece with a particularly well crafted Appendix. If less technically sophisticated readers out there want to know how statisticians estimate the impact of voting reforms on turnout, look here. Mike and Jonathan also show how you can take complex statistical results (in the Appendix) and translate them into policy recommendations. Political Scientists take note!
One thing I’d add to the mix: Maryland would be implementing same day registration in combination with early voting. Under the auspices of the Elections Initiative at the Pew Center on the States, a team of scholars and elections officials in Wisconsin have released a study analyzing how these two systems interact. Their work can be found here, at the University of Wisconsin Election Administration project page.