Election Day isn’t just about control of the U.S. Senate or House of Representatives, or even gubernatorial races in more than 30 states. Voters who head to the polls Nov. 4 will also decide which party controls 91 legislative chambers across the country. From northern Maine to San Diego, from the Orcas Islands in Washington to the Florida Keys, 6,049 of the country’s 7,383 state legislative seats are on the ballot this year.

Legislative seats from 46 states are on the ballot this year. That includes some 4,957 state House seats, and 1,092 state Senate seats. At least half the Senate and the entire House is up for grabs in 45 states; Nebraska, the lone oddball, has a unicameral, nominally nonpartisan legislature.

Elections officials will be busiest in New Hampshire, where 400 state representatives and 24 state Senate seats are on the ballot. In Pennsylvania, all 203 state House seats and half of the 50 state Senate seats will be decided.

More than 100 state House seats are up in Alabama, Arkansas, Connecticut, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Montana, New York, North Carolina, Oklahoma, South Carolina, Texas, Vermont and West Virginia.

Four states — Louisiana, Mississippi, New Jersey and Virginia — hold legislative elections in odd-numbered years.

Given that there are a total of 7,383 state legislative seats across the country, keeping tabs on the number of Democrats or Republicans in office at any one time isn’t always easy. Someone’s always retiring or quitting or, in the case of the California state Senate, getting indicted.

But the National Conference of State Legislatures keeps a pretty solid running tabulation [pdf]: As of June 9, the last time NCSL’s chart was updated, there were 3,448 Democratic state legislators, 3,836 Republicans and 75 members of different parties. Twenty-four seats were vacant.

Republicans control both chambers of the legislature in 27 states, after the Virginia state Senate flipped this month. Democrats own control in 18 states, and only four states — Iowa, Kentucky, New Hampshire and Washington — are split between the two parties (Remember, Nebraska is technically nonpartisan; Washington’s Senate gets an asterisk because a majority of members are Democrats, but Republicans and two centrist Democrats control the Senate through a unity coalition).

Here’s the map of party control:

Source: National Conference of State Legislatures