Ted Atkins fills out his primary day ballott in Southfield, Mich., on Feb. 28, 2012. (Joe Raedle/Getty Images)

Sad news for political junkies: This year’s election exit poll is set to include surveys from just 31 states — the first time in two decades that pollsters won’t survey voters in all 50 states.

The Post’s polling director Jon Cohen scooped the news this morning, noting that the decision by the National Election Pool — a joint venture of the major television networks as The Associated Press — likely robs election watchers across the country of the valuable political data they enjoy reviewing to determine voter decisions. But the void might also make it more difficult to determine potential voter trends and preferences ahead of the 2014 contests.

Here’s the list of states that will be excluded from coverage this year: Alaska, Arkansas, Delaware, District of Columbia, Georgia, Hawaii, Idaho, Kentucky, Louisiana, Nebraska, North Dakota, Oklahoma, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, West Virginia and Wyoming.

Ten of the 19 states have Senate races this year: Delaware, Hawaii, Nebraska, North Dakota, Rhode Island, Tennessee, Texas, Utah, West Virginia and Wyoming. At least one close contest — in North Dakota — could help determine the Senate balance of power. A handful of critical races in Hawaii, Rhode Island, Texas and West Virginia also could help tip the scales in the House.

In 2014, 16 of the 19 states have Senate races, and several of those contests also could help determine which party is in power (though only time will tell).

Midterm elections are different from presidential years in terms of the composition of the electorate, meaning it makes more sense to compare 2014 polling data with the 2010 or 2006 cycles. But political junkies, pollsters and reporters can agree: it’s still a problem to have less data.

Polling manager Peyton M. Craighill contributed to this report.

Follow Ed O’Keefe on Twitter: @edatpost