In the midterm elections of 1974 following party leaders telling Richard Nixon he had to resign due to the Watergate scandal – and for the "good of the party" – the GOP lost 48 seats in the U.S. House of Representatives, falling to only 144 GOP House members.  They also lost 4 seats in the U.S. Senate, falling to 38 GOP members. 

In the midterm elections of 1998, when the Democrats hung tough with a president during the height of a scandal about that president committing perjury in a federal court proceeding, the Democrats gained 5 seats in the U.S. House of Representatives and lost zero seats in the U.S. Senate.

On these pages last fall, I argued that even "NeverTrumps" should hope he wins, in part, because all the institutions of the government and society would work against Trump, but those same institutions would roll over for Hillary Clinton.  While I expected even some people in the GOP to work against President Trump, Republicans, especially members of Congress, should think very, very hard about those numbers above.

It's understandable that they may not like this outsider president.  Sure, it is a blow to one's ego for a non-professional to come into your business and take the top spot.  And being a part of the Washington elite, they do not want to cede power to an outsider.

Of course, the Democrats, particularly those in Congress, will want to work against the policies of President Trump and try to taint his administration to stop it from getting much done.  It is not their role to be the baseline support for a GOP president.  It is their role to work against a president of the opposite party.  They naturally do not want more than a minimum number of successes for the president, as that would likely harm their future electoral prospects.  They are also likely to be genuinely against many of the proposals of a GOP president.

GOP members of Congress may be tempted by something like the recent kerfuffle involving Jeff Sessions talking to the Russians to join the Democrats and fellow members of the political class in working to taint the Trump administration.  When they are tempted in this way, GOP members of Congress need to ask themselves, What reduces my power more?  President Trump getting some of his agenda passed or me losing my next re-election campaign?  GOP members of Congress need to ask themselves, Is it worth losing my seat to deter future outsiders from running? 

Each midterm election is different, and we have only a couple of observations.  Still, if you are a GOP member of Congress hoping to hold on to that body, you would do well not to abandon a president of your party on trivial issues of the day.  I would never say a member of a party should not abandon a president of his party no matter what the president does, but I will just point out that if you find that you must abandon your president, it will be at the risk of your seat and your party's seats in Congress.

I would also remind GOP members of Congress that the people across the aisle did not let perjury in a federal court case by a president of their party cause them to abandon him.  For me, if this is to be a one-sided moral decision, that raises the bar required to get me to abandon a president of my party.