Within polling places, does the scarcity of voting machines cause longer lines and thereby dissuade some people from voting? Are voting machines scarce in some areas because turnout would be low, irrespective of the availability of voting machines? In Ohio in the aftermath of the 2004 presidential election, the answers to these questions carried very real and significant political stakes. Consider the following from Franklin County, the second most populous county in the state. In precincts where voting machines were plentiful (i.e., where there were fewer registrants per available voting machine), turnout was especially high and John Kerry's share of the presidential vote was low. In contrast, in areas of machine scarcity (i.e., precincts with many registrants per available voting machine), turnout was lower and Kerry's vote share was higher. These relationships are shown in Figures 1A and 1B. Given the strong association between machine availability and the Kerry vote, if machine (un)availability was a cause of (low) turnout, then Kerry may very well have received fewer votes than he would have had more machines been available or had the distribution of available machines been less skewed toward precincts that were more supportive of George W. Bush.I appreciate input from SSRC Commission members Henry Brady, Martha Kropf, Walter R. Mebane, Jr., and Michael Traugott with whom I collaborated on the SSRC's “Interim Report on Alleged Irregularities in the United States Presidential Election of 2 November 2004” (Brady et al. 2004). I also thank Benjamin Bishin for comments on the paper. The Social Science Research Council and its staff, including Jason McNichol, Dashiell Flynn, and Sarah Alexander, provided generous support for this work. The views expressed in this paper are not necessarily shared by other SSRC Commission members or the Social Science Research Council.