In the House, Republicans won a net gain of thirteen seats, giving them their largest majority since the 1928 elections.

In state elections, Republicans won a net gain of two gubernatorial seats and flipped control of ten legislative chambers.

Major issues of the election included income inequality,[2] and the Affordable Care Act (commonly referred to as "Obamacare"), which Republicans sought to repeal.

[7][9][10] Although it generated much debate in early 2014, the Keystone Pipeline ultimately received little attention in the election, with environmentalists instead focused on fighting global warming and supporting the EPA's proposed regulations on greenhouse gas emissions.

The race in Louisiana headed to a run-off on December 6, 2014, in which Rep. Bill Cassidy (R) defeated 3-term incumbent Sen. Mary Landrieu 55.9% to 44.1%.

The Republican Party won 24 of the 36 state governorships for a net gain of two seats, as they picked up open Democratic-held seats in Arkansas, Maryland and Massachusetts and defeated incumbent governor Pat Quinn in Illinois, while Republican incumbents Tom Corbett of Pennsylvania and Sean Parnell of Alaska respectively lost to Democrat Tom Wolf and independent Bill Walker.

This cycle marked the first time an incumbent governor running for re-election in Pennsylvania lost in the modern era.

[21] In the table below, the US state governorships held by Democrats included: California, Colorado, Connecticut, Delaware, Hawaii, Kentucky, Minnesota, Missouri, Montana, New York, Oregon, Rhode Island, Virginia, Vermont, Washington, and West Virginia in addition to Washington, DC and Virgin Islands.

[22] They had lost control at the start of the year due to the election of Democratic lieutenant governor Ralph Northam.

[33][34][35] The states with the highest turnout were Maine (59.3%), Wisconsin (56.9%), Alaska (55.3%), Colorado (53%), Oregon (52.7%) Minnesota (51.3%), Iowa (50.6%), New Hampshire (48.8%), Montana (46.1%) and South Dakota (44.6%), all of which except for Iowa and Montana featured a competitive gubernatorial race and all of which except for Maine and Wisconsin also featured competitive Senate races.

[34][35] The states with the lowest turnout were Indiana (28%), Texas (28.5%), Utah (28.8%), Tennessee (29.1%), New York (29.5%), Mississippi (29.7%), Oklahoma (29.8%), New Jersey (30.4%) and West Virginia and Nevada (31.8%).

[41] California State Senator Roderick Wright (Democrat) resigned from office in September 2014 and was sentenced to 90 days in Los Angeles county jail for perjury and voter fraud.

In Pontiac, Michigan, local Democrats cited reports of voter harassment and intimidation by Republicans over questioning legally-cast ballots with election workers repeatedly having had to ask them to step aside.

[44] In June 2013, the Supreme Court invalidated part of the Voting Rights Act of 1965, permitting nine (mostly Southern) states to change their election laws without advance federal approval.

[52] In Bexar County, Texas, the Republican candidate for governor, Greg Abbott, was accidentally replaced on the ballot by David Dewhurst on one machine, on which 12 votes were cast before the problem was caught.