Editor’s Note: Scott Jennings, a CNN contributor, is a former special assistant to President George W. Bush and former campaign adviser to Sen. Mitch McConnell. He is a partner at RunSwitch Public Relations in Louisville, Kentucky. Follow him on Twitter @ScottJenningsKY. The opinions expressed in this commentary are his own.

CNN  — 

New polling from CNN and other outlets indicates that President Donald Trump’s job approval has improved since mid-December, and that the Democrats’ advantage over Republicans in the upcoming midterm elections has shrunk.

Scott Jennings

The reasons are obvious – the Republicans cut taxes, the economy is good, and people largely approve of Trump’s moves to break the logjam with North Korea. Basically, people like peace and prosperity. Or, as philosopher and fictional minor league baseball pitcher “Nuke” LaLoosh once opined: “I love winning, man. … It’s like better than losing.”

The danger for Republicans, of course, is that peace and prosperity won’t be enough to overcome the head winds they face. History is not on their side, as the party in power almost always loses seats in a president’s first midterm. And Trump, despite the polling improvement, still carries a job approval well below what any GOP strategist would tell you is necessary to overcome history.

Polling averages today put Trump between 41% and 42%, depending on which tracker you use (and whether you look at polls of voters or mix in surveys of adults, not all of whom are registered to vote). By comparison, let’s look at Gallup job approval numbers for President Barack Obama in the four polls leading into the 2010 midterm in which Republicans walloped the Democrats: 46, 45, 44, 45.

So even as Trump improves, Democrats should feel good that he has not improved enough to reach a level that would help his party overcome history. There are structural problems in the surveys (chiefly the gender gap) that might hold down Trump’s ceiling as he continues to struggle mightily to gain the support of non-Republican women.

What Democrats should be more concerned about is the generic ballot, where their advantage shrunk to just 6 points in March, according to CNN’s poll, a massive 10-point shift from their 16-point lead in February. While a 50% to 44% lead might sound good, remember that the sentiment reflected here essentially measures what the national popular House vote would look like but does not determine individual district results.

It is entirely possible for the Democrats to win more overall votes for the US House and not win the chamber. They could even win it by 6 points nationally and still not win a majority of seats, according to my favorite House handicapper, Dave Wasserman of the Cook Political Report.

While some people reflexively argue that gerrymandering is the culprit, Wasserman points out that other factors – such as the urban cloistering of the most partisan Democratic voters, incumbency and uncontested races – are also to blame for this possibility. According to the average of generic ballot polling as tracked by several aggregators, the Democrats’ lead is 6 to 7 points, right in line with CNN’s data.

So why are Democrats struggling to grow their generic ballot advantage? Because they continue to ignore three political realities: Most Americans aren’t as liberal as their outraged base voters (especially in urban areas); most voters want their taxes to go down instead of up; and most voters want the parties to work together when it makes sense. I’ll give you examples of each:

The census outrage: This week, Democrats were in a full-scale meltdown because the Trump administration decided to add a citizenship question to the 2020 census form. Democratic attorneys general readied their lawsuits. Liberal talking heads took to the airwaves. Democratic members of Congress wrote the most vitriolic statements their trembling hands could muster.

Meanwhile, most of America said: “What’s the big deal?” There is nothing remotely illogical or illegal about the United States figuring out how many citizens it has, as it seems like a common-sense thing to know. Our government can tell us how many zoologists are employed in each state but can’t count the total number of citizens? What a crock, and the associated outrage reminded me of Nancy Pelosi’s unhinged claim of a looming “apocalypse” should the Republicans cut taxes.

Repeal the tax cuts? Democrats overreached on the tax cuts and squandered credibility when discussing the economy. And now, not satisfied with the damage they did themselves by block voting against the Republican tax cuts in December, Senate Minority Leader Chuck Schumer has rolled out a plan to repeal the Trump tax cuts. They are calling it an “infrastructure plan,” but I know what it will be called in campaign ads this fall: Chuck and Nancy’s plan to raise your taxes. Republican strategists are chuckling about this boneheaded move.

Finally, the liberal resistance to all things Trump doesn’t square with recent polling conducted for the Democratic Congressional Campaign Committee. Here’s the way Axios reported it:

“New internal polling … suggests that Democratic candidates running in swing districts ‘must express a willingness to work with the President when his agenda might help the district.’ The survey also recommends that Democrats ‘not appear out of sync with what people believe about the economy.’ “

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    Squaring that strategy with the huge number of “nasty” Democratic primaries will be impossible as candidates seek to outdo each other with increasingly strident anti-Trump rhetoric. The “resistance” may nominate a bunch of candidates who can’t connect with average voters who like their lower taxes, job security and life in a world at relative peace, all thanks to Donald Trump and his Republican Party.

    I continue to favor Democrats slightly to win the House, but it isn’t a done deal. The Democratic enthusiasm advantage is real, and the historical trends are no joke. But like the 2016 presidential campaign, there are things in the water making this a choppier ride than it ought to be for the party out of power.