Super Tuesday marks the day that 24 states and American Samoa are scheduled to hold either primary elections or caucuses in the United States. This graph shows the number of counties in California that have a majority of Democrat or Republican registered voters in Presidential election years. Counties with a majority of Democratic voters include: Alameda, Imperial, San Francisco, and Santa Cruz. Whereas counties with a majority of Republican voters include: Placer, Mono, Sutter, and Shasta. Statewide, 67.3 percent (about 15.5 million people) of eligible voters are registered to vote in the 2008 primaries.