2008 debunks that -- but barely. Economic conditions and Barack Obama well fit the state in 2008, but not 2012.
No state has a perfect streak of going R in the last half of the twentieth century and into the 21st. Alaska, Idaho, Wyoming, North Dakota, South Dakota, Nebraska (except for CD-02 in 2008), Kansas, and Oklahoma haven't voted for a Democratic nominee for President since 1964. Arizona voted for its R Favorite Son in 1964 but for Bill Clinton in 1996. Indiana and Virginia were in that category until 2008 -- Carter won every former Confederate State except Virginia in 1976; Clinton never won Virginia, and won every state surrounding Indiana in both 1992 and 1996 but not both times.
On the other side is the District of Columbia -- although I suspect that Eisenhower would have won it in one of 1952 or 1956 had it voted. Stevenson well lined up the Southern racist vote if by default, and that might have pushed DC toward Ike had it been voting for President. Minnesota was the lone state voting for Mondale in 1984 -- and barely! -- for a Favorite Son. Massachusetts went twice for Reagan but was the only state that voted for McGovern.
Kansas is probably now the most consistently Red state. It was never part of the South; it has been ethnically homogeneous for most of its history (although there is a large Hispanic immigration into Kansas now); it is rural. Kansas City, Kansas and perhaps Lawrence are fairly liberal, but Wichita is not. Its most famous industry is private aircraft whose customers are usually very right-leaning. The R hold on the South (in that sense I include such border states as Kentucky, West Virginia, Missouri, and Oklahoma) is shaky if the Democrats ever win back the poor whites who used to reliably vote for Democrats. Demographics will eventually make Arizona and Texas become targets for Democratic campaigns. If Republicans ever double down on religious bigotry they could lose Idaho, Utah, and Wyoming due to large Mormon populations and the Dakotas and Nebraska due to large Lutheran populations. (They would lose about everything else, to be sure, and probably their future).
Keep in mind that Kansas is not majority-rural, even though it has a larger rural population than most states (35%, compared to about 19% nationally). The rural population is declining in Kansas; places like Johnston and Sedgwick Counties are increasingly more influential in the state's politics.
