The Obama factor in the 2014 midterm election

US President Barack Obama speaks during a rally at North Division High School on Oct. 28, 2014 in Milwaukee, Wis. (Photo by Brendan Smialowski/AFP/Getty)
US President Barack Obama speaks during a rally at North Division High School on Oct. 28, 2014 in Milwaukee, Wis.

Midterms are always seen as a referendum on the incumbent president. It hasn’t helped Democrats that President Obama’s job approval ratings are even lower than they were in 2010, when his party lost control of the House of Representatives.

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The NBC News national exit poll found that just 44% of voters approve of Obama’s job performance, while a majority -- 55% -- disapprove. This is a reversal of fortune for the incumbent from his re-election bid just two years ago, when 54% approved and 45% disapproved. And it is almost identical to the voter ratings given at his first midterm, when 44% gave the president a thumbs up, and 55% rated him negatively.

One indicator of how much of a motivating factor Obama may have been in this year’s midterm is the percentage of voters who strongly disapprove of the president’s performance. This stands at 42% among all voters – and a substantial 74% among Republicans.

On the other side of the ledger, the president’s own partisans do not muster enough enthusiasm to offset the intensity of Republican dissatisfaction. While 8-in-10 Democrats approve of the job Obama is doing, just 38% say that they strongly approve of their president’s performance.

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The impact of presidential disapproval in this election cannot be boiled down to a single issue. For example, the Affordable Care Act – or “Obamacare” – is likely to be Obama’s signature domestic policy legacy when he leaves office. It has been the subject of nearly a half-billion dollars of mostly negative political advertising since 2010. But voters today are actually divided on the issue, according to the NBC News national exit poll. Nearly half – 49% -- say the health reform law went too far. But the other half say the reforms were either about right – 21% -- or didn’t go far enough – 25%.

These views are very partisan, with 43% Democrats today saying the law didn’t go far enough, and 78% of Republicans saying it went too far. This may be a divisive issue, but it wasn’t necessarily the most pressing issue on voters’ minds on Election Day. Just 25% chose health care as the most important issue facing the country, placing it a distant second to the economy, at 45%.

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The NBC News national exit poll asked voters whether the president was a factor in their vote for House of Representatives. Overall, 33% said their vote choice was made in part to express opposition to Obama, 19% said their vote was in support of Obama and 45% said Obama was not a factor in their House vote.

Not surprisingly, most Republicans – 59% -- said that opposing Obama was a reason for their vote choice, but fewer Democrats – just 40% -- said that supporting Obama was a factor in their vote. Among independent-minded voters, the results are mixed – 31% of independents said their House vote was influenced by opposition to Obama, 12% said they vote to support of Obama, and a 55% majority said Obama was not a reason for their vote choice.

The extent to which the Obama factor influenced individual outcomes in House races across the country is still being tallied. But it does appear that whatever role the president played was, on the whole, more negative than positive for Democrats.

Visit NBC News Decision 2014 for more exit poll results and election returns.