In the aftermath of the American Civil War during Reconstruction, Louisiana was governed by Republicans. They were soon replaced by Democrats who established Jim Crow laws that eliminated Black political participation for nearly 100 years. Between 1880 and 1960, the state voted Republican for president once (in 1956), and exclusively elected Democrats to all statewide offices and they dominated the state legislature and congressional delegations.
In the early 20th century, Louisiana retained a pocket of Republican strength centered around the sugar parishes west of New Orleans, where farmers favored the GOP's position on protective tariffs. According to The Louisiana Elections of 1960, whose authors include the late sociologist Perry H. Howard, from 1920, the year of the election of Warren G. Harding as U.S. President until 1956, the reelection of Dwight D. Eisenhower, "a number of parishes, many in close proximity, have consistently supported the Republican party at close to or significantly above the presidential Republican vote average. Apart from some of the urbanized parishes, the majority of these parishes are in south Louisiana; in fact, they form a cluster in the sugar cultivation area west of the Atchafalaya swamp and along Bayou Lafourche and the Mississippi River below Baton Rouge."[2]
In the decades following the beginning of the Civil Rights Movement and a concomitant reaction against cultural liberalism, the Republicans gained strength in the conservative suburbs of New Orleans and Baton Rouge and for a time in Caddo Parish. The GOP drew increasing support among rural voters elsewhere, including parts of North Louisiana and Southeast Louisiana. These patterns follow trends in other southern states as white control of state Democratic Party structures weakened, and the region became more diverse and more prone to adopt the two-party behavior characteristic of most of the nation.[3]
In time, Republicanism took root in the Shreveport-Bossier City area of northwest Louisiana, with increasing strength, added from Ouachita, Lincoln, Rapides, East Baton Rouge, and Lafayette parishes plus most of the suburban parishes about New Orleans. Two of the smaller Republican-leaning parishes in North Louisiana are La Salle and West Carroll Parish.
Since the construction of the Lake Pontchartrain Causeway in the mid-1950s, the Northshore Region began demonstrating increasingly Republican leanings, first and most notably in Saint Tammany Parish, which as of 2010 had the highest percentage of registered Republican voters in Louisiana. It was the first parish since the Reconstruction Era to leave the Democrats merely a plurality and the first to experience a Republican majority.
In the 1964 election, Republicans won the state by double digits, their largest victory since Reconstruction, as Democratic support collapsed in the Northern part of the state following the passage of the Civil Rights Act of 1964. The Republican victory was not as commanding here as it was in other Deep South states, as they stayed under 60% of the vote. The state soon became a swing state by voting for the nationwide winner in every election between 1972 and 2004.
21st century
The political balance in Louisiana was heavily affected by the post-Hurricane Katrina departure from New Orleans. Heavily Democratic New Orleans lost some 1/3 of its population. The overall effect reduced the Democrats' base of support in the state and turned Louisiana into a Republican-leaning state thereafter. New Orleans remained Democratic, electing Mitch Landrieu as mayor in February 2010. In the 2008 elections, Louisiana sent a mixed result, with the election of U.S. Senator John McCain for President and the reelection of Democratic U.S. Senator Mary Landrieu. The other senator, at the time, was Republican David Vitter.
Since that election, Republicans have rapidly come to control nearly every federal and statewide office. Both US Senators are Republicans. Republicans also hold five of the six U.S. Representative seats from Louisiana. Every statewide office, with the exception of governor, is held by a Republican, and both chambers of the state legislature are majority Republican. By contrast, in 1960, not a single Republican served in either house of the Louisiana legislature. The first Republicans to serve in the legislature since Reconstruction were not elected until 1964, and both—Morley A. Hudson and Taylor W. O'Hearn—came from Shreveport.
In 2010, several Democrats switched parties bringing the statehouse under Republican control. In 2011, the special election victories of Fred Mills and Jonathan Perry switched the balance of power in the state senate, leaving Republicans in control of the state legislature for the first time since Reconstruction. Also, the party switch of Attorney General Buddy Caldwell caused the Republican party to control every statewide office. However, this was broken in 2015, when Democrat John Bel Edwards won the governor's race.
Republicans won the first Senate seat since Reconstruction in 2004, with the election of David Vitter. He became the first popularly elected Republican Senator as well. In 2014, Republicans won both Senate seats for the first time since 1872.