The most that can be achieved, and it’s a lot, actually, is to convey to the swing voters — the independents, suburban women and moderate Republicans who delivered the House to the Democrats in the 2018 midterms — just how much this president is ready to put himself above the law. And, therefore, four more years of his presidency, when he would no longer be “restrained” by the need for re-election, would be catastrophic for our country’s unity and for the institutions and norms that have sustained it since 1776.

I am convinced that more Americans are worried about the country’s cohesion and its institutions being ripped apart by Trump than Trump realizes. It’s a key reason his approval rankings remain largely flat while our stock markets soar. I also believe that the Trump team has overestimated how easy it will be for it to just keep hiding the most important evidence and witnesses now that the impeachment trial has begun and many Americans are tuning in to this issue for the first time.

And when they do, variations of that simple question — “Why would an innocent man, and a jury interested in the truth, not want all the evidence out and all the witnesses to testify? Wouldn’t you if you were innocent?” — will take on even more power.

Republican senators have been able to dodge that question for months while the matter was in the House, but not any longer. And you can already see how uncomfortable it makes them by the way Senator Martha McSally literally ran away from and denounced a CNN reporter when he asked her if the Senate should consider new evidence as part of the impeachment trial. There is a reason McSally fled.

A CNN poll released Monday night found that 69 percent of Americans want the Senate to call new witnesses, while 26 percent do not.

Democrats still need to come up with a compelling candidate against Trump. But the midterms told us that there is an important coalition of independents, moderate Republicans and suburban women no longer so sold on Trump.

In 2016 they disliked Hillary Clinton and were willing to give Trump a chance, telling themselves, “How bad could it be — and hey, anyway, we have the Constitution to protect us.” Then they witnessed just how bad it could be and that the Constitution in Trump’s hands could not protect us. Democrats running in swing districts in 2018 also kept it simple, focusing on Trump’s attempts to destroy Obamacare and coverage of pre-existing medical conditions.