How a booming US economy can cost Trump his presidency

Strong economies tend to boost incumbents yet the Democrats are riding high in midterm election polls. Why?

The US economy is growing, inflation has finally hit the US Federal Reserve's 2% target and unemployment is quite low - and at an all-time low for African-Americans and Hispanics. For the first time in memory, there are more job openings listed by US companies than there are unemployed people. Such conditions usually foreshadow rising real (inflation-adjusted) wages, which would indicate that American workers, many of whom were left behind in the anaemic post-crisis recovery, might finally reap benefits from the strong economy.

Electoral models predict a strong economy favours the party in power and a weak economy dooms it to crushing losses. And yet, with the economy in its best condition in more than a decade, most polls show a substantial Democratic party lead in the run-up to the midterm congressional elections in November. Moreover, most political pundits predict the Democrats will take back control of the House of Representatives. And some even foresee a "blue wave" in which Democrats also retake the Senate, despite having to defend far more seats than the Republicans. In several recent special elections, Republicans have held on by far narrower margins than in past elections for the same congressional seats.

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Midterm elections are almost always a referendum on the president and his policies