If the definition of insanity is doing the same thing over and over again and expecting a different result, then perhaps the Democrats on a crusade to impeach President Trump should think twice about the road they are heading down.

It’s one thing to hold more investigations and try to get President Trump’s tax returns. It is quite another thing to turn the entire machinery of Congress over to the impeachment process while blocking compromises on health care, immigration, infrastructure and other important legislation.

The warning signs of partisanship taken too far come from what happened in 1998 with the impeachment of President Clinton by the House, and from the recent Senate confirmation battle that raged over the nomination of now-Supreme Court Justice Brett Kavanaugh.

In the Clinton case, voters reacted negatively to Republicans who tried to turn unsavory personal behavior into crimes to support the impeachment of the president in the House of Representatives. Clinton was acquitted on charges of perjury and obstruction of justice at his Senate trial, so the effort to remove him from office failed.

In the Kavanaugh confirmation fight, voters reacted negatively to Democrats on the Senate Judiciary Committee who went overboard with Spartacus moments and for the way they handled allegations of sexual misconduct.

Voters made clear in both the Clinton and Kavanaugh cases that they want their elected representatives in Congress to get the business of lawmaking done and not focus on partisanship.

Back in 1998, House Republicans considered Bill Clinton an illegitimate president who they believed the American public would support removing from office if Independent Counsel Ken Starr reported that Clinton lied under oath. The Starr report was a blockbuster, complete with graphic descriptions of Oval Office sexual activity between Clinton and then-White House intern Monica Lewinsky and stained-dress evidence.

But the plan backfired. In the 1998 midterm elections, Republicans actually lost seats in Congress as we Democrats used the theme “Progress, not Partisanship,” and the whole imbroglio toppled House Speaker Newt Gingrich, R-Ga.

News coverage of Clinton’s involvement with Lewinsky took a year from start to finish. In the end, even though it was just a partisan vote, the headlines blared “Clinton Acquitted.” After it was over, Americans never wanted to talk about it again, nor did the Republicans. Clinton’s poll ratings soared.

It takes the votes of 67 senators to convict a president impeached by the House and remove him from office. The midterm Senate elections last month will result in a Senate made up of 53 Republicans and 47 Democrats beginning in January.

But the pressure from the Democratic base to impeach Trump will be enormous. So House Democrats are more likely to go down the impeachment road that – without significant Republican support – will come off as partisan overreach.

As a result, if the new Democratic majority that will rule the House votes to impeach President Trump, even if every Senate Democrat votes to convict him they would need to pick up the support of 20 Republican senators to remove Trump from office.

Does anyone seriously think that there are more than a handful of Republican senators at most who would favor Trump’s conviction and ouster, even in the face of a damning report from Special Counsel Robert Mueller? The chances of that happening are virtually nonexistent.

So does an impeachment fight that is almost guaranteed to end with President Trump still in the Oval Office benefit Trump or the Democrats?

Does the headline “Trump Acquitted” after a Senate trial help anyone but Trump, albeit after a painful and distracting rollercoaster process?

Maybe Democrats just want the catharsis of impeaching their nemesis, but such satisfaction is likely to be fleeting.

Sure, the Mueller report is going to be a collection of greatest hits against President Trump – a prosecutor’s tale carefully woven over two years to turn every utterance by Trump into obstruction and every contact with a Russian into collusion.

But, absent the caveat of some truly new and devastating information, the public is smart enough to distinguish the case against President Trump from the kind of actual obstruction of justice by President Nixon, who authorized hush money to organizers of the break-in at Democratic National Committee headquarters.

The whole process of Mueller’s investigation of Russia’s interference in our 2016 presidential election and possible collusion between the Trump campaign – or Trump himself – and Russia to win the election has been flawed from its inception. Now it seems to be focused on payments for alleged consensual affairs and trying to criminalize them.

There have been a number of questionable actions by people in the FBI and the Justice Department before and throughout the Mueller probe. Eventually, the next attorney general will likely appoint a special counsel to investigate all of the retired, resigned and fired officials and whether their actions were politically motivated.

So come January, the Democrats in the House will have a choice. They can accept the Mueller report and move on. Or, they can hold endless hearings all over again run by Rep. Jerrold Nadler, D-N.Y., who is expected to chair the House Judiciary Committee, and then vote to impeach the president or censure him for the actions described in the Mueller report.

The smartest move Democrats could make would likely be to approve some kind of censure motion against President Trump after a few hearings and then say the American people will decide in the 2020 election who should be president for another four years.

But the pressure from the Democratic base to impeach Trump will be enormous. So House Democrats are more likely to go down the impeachment road that – without significant Republican support – will come off as partisan overreach.

The fight to impeach President Trump will inflame passions on both sides and will dominate news coverage for months. Democrats seeking the party’s nomination to run for president in 2020 will be lost in the shuffle of the bright media spotlight on the effort to remove Trump from office. Morning, noon and night, impeachment will be what we are all talking about.

President Trump, like it or not, maintains significant and passionate public support that has even withstood unbelievably damaging tapes and countless critical stories and revelations in the media.

Trump’s approval ratings in polls right now are above where Presidents Clinton and Obama were at this same stage of their presidencies. According to the most recent RealClear Politics average of polls, Trump has an approval rating of about 43 percent and a disapproval rating of 52 percent.

The U.S. president is not viewed as negatively as French President Emmanuel Macron, whose approval ratings are below 20 percent.

In fact, members of Congress have Macron-like approval ratings, precisely because of their failure to get things done for the American people.

The question confronting Democrats at the start of the new year will be whether they want to repeat what the Republicans did in 1998, and whether it will have the same outcome. The most likely answers right now are yes and yes.