Source: https://fivethirtyeight.com/features/what-some-early-high-quality-polls-can-tell-us-about-the-race-for-the-house/

«the Monmouth polls imply a 6-point shift toward Democrats from the partisan lean, on average. That’s right in line with the 6- to 9-point lead Democrats have held in generic-ballot polling over the weeks that Monmouth has conducted these polls. It’s well below the average 16 points by which Democrats have outperformed partisan lean in federal special elections since President Trump’s inauguration, but that’s not too surprising: Special elections, by definition, do not feature incumbents (who have a built-in advantage)

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• 46 percent of Americans say they are extremely interested in the November elections according to a Fox News poll. That’s compared to 29 percent around this time in 2014 and 28 percent in 2010.»