On Saturday, CNN election analyst Harry Enten broke down how President Donald Trump may be performing worse in competitive districts than Republicans are willing to admit.
"Look at the live interview polls (and all surveys, for that matter) taken this summer that asked about race for the presidency and the race for Congress. Counting each pollster only once in the average, former Vice President Joe Biden leads Trump by 10 points in these polls," wrote Enten. "Democratic House candidates are ahead of the Republicans by 8 points on the generic congressional ballot in these same surveys."
This, Enten argued, could be a big reason why the internal polls released by House Republicans in the past few weeks have generally omitted the presidential preferences of the respondents — a sign that these numbers could be even worse than the candidates', which the GOP doesn't want public.
"The fact that Biden's lead is wider than the House Democrats' edge is unusual. If it holds, it would be ahistoric," wrote Enten. "You'd expect that Trump would be doing better than Republicans running in the House. The simple reason is that more Democrats (i.e. the majority party) have an incumbency advantage in the House, while Trump enjoys that same advantage for the presidency."
Incumbent presidents generally enjoy a significant advantage over non-incumbent presidents in elections, according to data. No incumbent president has lost re-election since George H. W. Bush in 1992. Indeed, Enten noted, in the last 80 years, "the minority party in the House has done better in the presidential race 13 of 15 times when they either control the White House or the incumbent president is not running for re-election. The vast majority of the time, it's not even close."
"Perhaps the good news for Trump is that if he is doing worse than the fundamentals, then he has room for improvement without the political environment changing too much," concluded Enten. "Of course, even if Trump was doing as well as Republican candidates for the House, he would still be trailing."
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