The electoral college has narrowed serious campaigning for president to so few states that analysts now talk of no more than a couple of dozen counties, in a third as many states, as being especially crucial. None of those counties, obviously, are in Idaho.

Like every state it borders (debatably excepting Nevada), Idaho’s electorate votes for president are already very nearly locked. The Gem State’s four almost (remember: the voter isn’t over till it’s counted) certainly will go to Republican Mitt Romney. No surprise there. That puts Idaho in line with Montana, Wyoming and Utah, and on the other side from Washington, Oregon and (probably) Nevada.

Presidential years usually are good years in Idaho for Republicans (the reverse applies in most blue states), but that can vary. An especially strong Republican vote for president can carry down the ballot, shifting otherwise races. The number of legislative seats Democrats win this fall, for example, may relate to just how large a majority Romney wins.

This fluctuates more than you might think.

Taking the very long range of history, the highest vote percentage (78.1%) Idaho has ever given to a presidential nominee – Ronald Reagan included – was to a Democrat, though for that you have to go back to 1896, when the nominee was William Jennings Bryan. The last Democrat to win Idaho was Lyndon Johnson in 1964, though he led by only about 5,000 votes over Barry Goldwater, who went down to major crashing defeat nationally.

Since 1968, Republicans have won every time with decisive margins, but less uniformly as you might think. Reagan peaked at a very strong 72.4% in 1984, but his successor George H.W. Bush took just 62.1% – quite a comedown. And in 1992, eight years after Reagan’s smashing win, when Ross Perot won a piece of the vote, Bush got only 42%. (Is that an indication that, under certain circumstances, a portion of those Republican votes can be peeled off?) Four years later Robert Dole again won an outright majority, but only barely, at 52.2%. And the 90’s was when the Idaho Democratic Party already was in collapse, when it was elected near-record low numbers of legislators and county officials.

George W. Bush did considerably better, getting about two-thirds of the Idaho vote in his two races. But in 2008, a year when Idaho Democrats did a little better locally than they often had in presidential years, John McCain was back down to 61.2%. The odds are Romney will do a bit better, but by how much we have yet to see. The Republican presidential norm seems to be in the low sixties.

One other note is about counties. Blaine County is the only Idaho county to have voted Democratic in each of the last five presidential contests, and it was the only one in Idaho to do so in 2000 and 2004. (Before 1992 it had not done so since 1964.) But in 2008 only two other counties, Latah and Teton, joined it, and in 1996 just four counties (Blaine, Latah, Nez Perce and Shoshone) went Democratic. The pattern has shown some shift away from the old Democratic resource counties like Shoshone and Nez Perce, and toward counties with other bases, like resort-oriented Blaine and Teton. What will the pattern show this time?

That may turn a great deal on just how close this presidential contests turns out to be.