ABC News' '14 For 14': The 2014 Midterm Election Races That Matter

— -- intro: The 2014 elections are providing a valuable snapshot of a changing nation. With a colorful and ambitious cast of candidates, they offer a wild ride of colliding ambitions -- with control of the national agenda on the line.

Throughout the year, ABC News' "14 for 14" project will document 14 races that matter between now and November. It will be a dynamic list of the campaigns -- limited to 14 at any given time -- that individually and collectively provide the big picture of where the country stands, and where we are headed.

All 435 House seats will be filled this year. So will 36 Senate slots, and 36 governors are scheduled to be elected, too. The 500-plus big nationally significant races are fascinating in their smallest details, for the personalities and issues that animate individual elections more than the ultimate scoreboard results.

ABC News Political Director Rick Klein: Why We Chose These Races

Listed below are the slate of 14 races chosen by the ABC News Political Unit:

quicklist: 1title: Senate -- Kentucky

text: The Kentucky Senate race will be the most watched 2014 contest of them all, and the stakes could not be higher.

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quicklist: 2title: Senate -- Arkansas

text: Vulnerable incumbent Sen. Mark Pryor takes on a well-funded GOP opponent with a central-casting resume, Rep. Tom Cotton, in a battle that could determine control of the Senate.

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quicklist: 3title: Senate -- Georgia

text: A crowded Republican primary could produce a far-right nominee, leaving an opening for Democrat Michelle Nunn, the daughter of a former senator.

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quicklist: 4title: Senate -- Louisiana

text: Sen. Mary Landrieu, a three-term Democrat, fights to hold on in the South in a must-win Senate contest for Democrats.

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quicklist: 5title: Senate -- New Hampshire

text: Sen. Scott Brown, the all-but-declared challenger to incumbent Democratic Sen. Jeanne Shaheen, has turned a sleeper race into what is likely to be one of the most hotly contested battles in the country.

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quicklist: 6title: Senate -- Iowa

text: The race is on to replace retiring Democratic Sen. Tom Harkin in Iowa, with the GOP increasingly eyeing this contest as a potential pick-up opportunity.

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quicklist: 7 title: Senate -- North Carolina

text: Democratic Sen. Kay Hagan rode to victory in 2008 on President Obama’s coattails. Now, she could be headed out of office if voters identify her too closely with the unpopular president.

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quicklist: 8title: Senate -- Kansas

text: Three-term incumbent Sen. Pat Roberts is facing his toughest reelection bid yet in a state that has only sent Republicans to the Senate since 1932.

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quicklist: 9title: Governor -- Florida

text: Republican-turned-independent-turned-Democrat Charlie Crist's political evolution has him trying to retake the governor's office from a tea party force, Gov. Rick Scott.

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quicklist: 10title: Governor -- Texas

text: An epic battle in the most populous red state pits new Democratic star Wendy Davis against well-regarded Republican Attorney General Greg Abbott.

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quicklist: 11title: Governor -- Wisconsin

text: Gov. Scott Walker looks to burnish his national resume by winning the governorship for the third time inside of four years, but Democrats would love to scratch his name off the 2016 list.

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quicklist: 12title: House -- Colorado's 6th Congressional District

text: A pure Western tossup, with liberal and conservative pockets of voters squaring off in a battle for who can turn out its side, in a state at the forefront of new social policies.

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quicklist: 13title: House -- Arizona's 2nd Congressional District

text: It's round two for Democrat Rep. Ron Barber of Arizona and his 2012 Republican challenger, retired Air Force Col. Martha McSally in the seat once held by former Rep. Gabby Giffords.

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quicklist: 14title: Land Commissioner -- Texas

text: The Bush dynasty extends to a new generation, with George P. Bush -- the son of former Florida Gov. Jeb Bush and the grandson of former President George H.W. Bush -- seeking his first political office, with his Hispanic heritage a potential asset in changing Texas.

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