Presidential vote and House vote

I've heard some people say that the only way the Democrats take back the House is if Obama wins in a landslide. His coattails could carry the party to victory in the House. There's a certain logic to it, as people often vote down the ballot how they vote for President. History shows us otherwise. There have been three recent landslides in re-election, Richard Nixon in 1972, Ronald Reagan in 1984, and Bill Clinton in 1996.

In their election, Nixon and Clinton had House votes that were pretty close to their two party Presidential vote. The Republicans were weak in 1980, so Reagan could only take them so far. Yet when Reagan and Nixon won big in re-election, their party did worse in the House.

The two party numbers are used to compare apples to apples in both the President and the House. The presence of Ross Perot threw off the Presidential numbers. The House vote suggests that we probably should probably assign more of Ross Perot's votes to Clinton, instead of going proportionally.

I don't have a definitive idea for why this happens. The voters each added in their re-election runs probably voted regularly for the other party and so no reason not to keep doing that. That might explain the disparity in the re-election, but not the House vote drop.

This chart adds three Presidents who ran for re-election who didn't win big. Carter's presidential vote and House vote both sharply declined. The Republican House vote percentage in George Bush's election year was the lowest any President has gotten when he won and the lowest when a candidate lost since 1960. So, it shouldn't be all that surprising the numbers went up.

The most hopeful model for Barack Obama is George W. Bush. His percentage when he was elected was much lower than Obama. That might make the comparison moot. Bush's party didn't do that well in the re-election. It's possible that if Bush had gotten 54-55% of the vote, the Republican Party wouldn't win any more votes.

I can't definitively say that Democrats won't get 55.6% of the vote if Obama wins in a landslide. There's just no reason to think they will do any better than they'd do if he lost. Of course, if he loses that means the Republicans will have an initial Presidential election and that's often very good for his party.