The economy is better for President Trump's first midterm election than it was for either of Barack Obama's two midterm elections — largely because it has been steadily improving since the 2008 financial crisis.

Why it matters: In 2010, Democrats lost the House, and in 2014, they lost the Senate — two losses for Obama, and both under weaker economies than Trump has now. Yet it's very possible that Republicans will lose the House under Trump's watch despite the strong economy.

“People get credit for what happens on their watch, whether they deserve it or not," said Doug Holtz-Eakin, a GOP economist. He added, though, that the tax cut and GOP deregulation effort have also helped.

The bottom line: Trump can talk up the strong economy, but if Republicans lose the House on his watch, it will be hard to explain for any other reason than his unpopularity.