Congress almost always votes with Trump as 2018 midterms loom. Bad idea, polls suggest.

Nearly two-thirds of Americans disapprove of the job Donald Trump is doing as president. It’s a remarkably dismal number for a president at any time, but especially so early in his term.

It’s clear that the dissatisfaction is not only because of scandals and poor behavior, but also because his policies are deeply unpopular.

Consider this: Just 28 percent of Americans support Trump’s decision to withdraw the United States from the Paris climate agreement. The health care bill he celebrated has approval ratings in the teens. And a full 62 percent disagree [PDF] with his attacks against the Clean Power Plan and other Obama-era pollution limits.

In spite of this, hundreds of members of the U.S. House and Senate, many of whom face re-election next year, continue to vote with the president nearly all the time.

Here’s why this matters: Presidential approval is one of the most important determining factors in midterm elections, and Trump’s ratings could have consequences for lawmakers who now follow his lead.

Unpopular presidents a risky bet

As the Gallup Poll noted in advance of the last midterm election 2014, a president’s “standing with voters is usually a significant predictor of election outcomes.” When presidents are unpopular, Gallup reported, “their party typically loses a substantial number of seats in the House of Representatives.” 

That makes congressional voting patterns in 2017 so much more remarkable.

Even “moderates” support Trump 90% of the time

According to analysis by FiveThirtyEight, 229 House members sided with Trump’s position more than 90 percent of the time – and 102 have a 100-percent Trump score.

With some important exceptions, even members who like to be considered moderates nearly always support the president’s positions, as FiveThirtyEight shows in its breakdown of who voted how.

Who favors contaminated food and dirty water?

When the House voted to overturn a rule limiting methane pollution from oil and gas wells on public lands, 221 members voted with Trump’s position. Some of them come from districts the president didn’t even win – including Rep. David Valadao of California whose district Trump lost by double digits.

Most of those members also voted for legislation that would add red tape and make it harder to use good science to create safeguards for heath, clean air and other issues.

If these bills become law – and make it more difficult to protect people from contaminated food and dirty water – it won’t comfort the public to learn that their elected officials felt the need to support the president.

I doubt these lawmakers actually like the idea of more air pollution and climate disruption – or think it’s popular at home – but maybe pressure from their congressional leadership was more important to their calculation.

When voting records become toxic

This lockstep voting doesn’t apply to everyone in Congress, of course.

There were many votes against these bills, including by some Republicans such as Reps. Ileana Ros-Lehtinen of Florida and Brian Fitzpatrick of Pennsylvania; and by Sens. John McCain (Ariz.), Lindsey Graham (S.C.) and Susan Collins (Maine), who opposed the methane pollution bill.

But for many others, it will be very difficult to differentiate themselves from the unpopular chief executive.

Recall that in 2008, part of Sen. John McCain’s strategy in the presidential race was to use his maverick reputation to separate himself from President George W. Bush.

Except, there was video of McCain from the primary season reminding Republicans that he voted with the president 90 percent of the time. That statistic was politically toxic and the Obama campaign spent a lot money on ads featuring the clip.

If our representatives in Congress keep walking toward a political cliff with this unpopular president – tearing down health protections, gutting the U.S. Environmental Protection Agency budget, and weakening clean air and water rules – they will find their opponents running very similar TV ads in 2018.

It’s dangerous to overlook Pence’s environmental record. Here’s why.