The California Democratic Party is the affiliate of the Democratic Party in the U.S. state of California. It is headquartered in Sacramento. With 43.5% of the state's registered voters as of 2018, the Democratic Party has the highest number of registrants of any political party in California. It is currently the dominant party in the state, and is one of the strongest affiliates of the national Democratic Party. The party currently controls the majority of California's U.S. House seats, both U.S. Senate seats, the governorship, and has supermajorities in both houses of the state legislature. History 1850s Since the beginning of the 1850s, issues regarding slavery had effectively split the California Democratic Party. By the 1853 general election campaign, large majorities of pro-slavery Democrats from Southern California, calling themselves the Chivalry (later branded as Lecompton Democrats), threatened to divide the state in half, should the state not accept slavery. John Bigler, along with former state senator and lieutenant governor David C. Broderick from the previous McDougall Administration, formed the Free Soil Democratic faction, modeled after the federal Free Soil Party that argued against the spread of slavery. The Democrats effectively split into two camps, with both the Chivalry and Free Soilers nominating their own candidates for the 1853 election. By 1857, the party had split into the Lecompton and Anti-Lecompton factions. Lecompton members supported the Kansas Lecompton Constitution, a document explicitly allowing slavery into the territory, while Anti-Lecompton faction members were in opposition to slavery's expansion. The violence between supporting and opposition forces led to the period known as Bleeding Kansas. Splits in the Democratic Party, as well as the power vacuum created by the collapse of the Whig Party, helped facilitate the rise of the American Party both in state and federal politics. In particular, state voters voted Know-Nothings into the California State Legislature, and elected J. Neely Johnson as governor in the 1855 general elections. During the 1859 general elections, Lecompton Democrats voted for Milton Latham, who had briefly lived in the American South, as their nominee for governor. Anti-Lecomptons in turn selected John Currey as their nominee. The infant Republican Party, running in its first gubernatorial election, selected businessman Leland Stanford as its nominee. To make matters more complicated, during the campaign, Senator David C. Broderick, an Anti-Lecompton Democrat, was killed in a duel by slavery supporter and former state Supreme Court Justice David Terry on September