Here’s the only way Democrats can impeach Trump

• The Democrats are making it too easy for Republicans to quietly back Trump.
• The GOP won't abandon Trump if that helps the Democrats.
• The Democrats need to pipe down and let Trump hurt himself.

There's one problem with the growing drumbeat to oust President Donald Trump from office: it's being led by Democrats. And when one of our major parties is stumping for something big to happen, you can bet the other one will do all it can to stop it.

In that sense, this Democratic Party effort to oust the president is doomed for now.

We've seen this before when it comes to the unique political fortunes of Donald Trump. Even after he ran one of the nastiest primary campaigns in history against a crowded Republican field, those opponents he bashed ended up endorsing him in the general election.

Such is the way of things in American politics. As another very reluctant Trump-backer, House Speaker Paul Ryan, put it last summer: "It's a binary choice... it's either Donald Trump or Hillary Clinton." And it turned out almost every Republican hated Hillary Clinton more than they loathed Donald Trump.

It's happening again now. On Wednesday morning Ryan reminded the news media at the very beginning of a news conference that there are a lot of people who, "want to harm the president," and that "clearly, a lot of politics is being played" in these leaks concerning President Trump's meetings with former FBI Director James Comey and his dealings with Russian officials.

Getting back to the Democrats, their entire agenda can now be summed up as: Impeachment, resignation or bust. They've put all their eggs in this basket. And if they fail, a lot of their voters will clearly ask what good the current leadership is if it can't even oust a man so much of the Democratic base sees as nothing short of the devil.

So far, they're doing it wrong. Democrats appear unable to let President Trump sink himself. As they jump on every statement, they taint every one of his missteps with their own loud and angry voices. Knee jerk critics like Senate Minority Leader Chuck Schumer and DNC Chairman Tom Perez are foolishly making the issue very much about them and their party as well. That makes it that much easier for the Republicans to at least tacitly support President Trump.

The party-line divide is a big problem for the Democrats, because they are the minority party and have a long way to go to get enough votes in the House to begin impeachment proceedings. Another long shot idea is for a majority of the cabinet to invoke its 25th Amendment powers and remove President Trump if he is: "unable to discharge the powers and duties of his office."

Even if his all-Republican cabinet pulls that off, a two-thirds vote by Congress would still be needed to confirm the cabinet's judgment.

History is also against the Democrats at this point. They should remember that the only two presidents ever to be impeached, Andrew Johnson and Bill Clinton, were put in that position by the majority parties in Congress at the time.

Republican President Richard Nixon was not impeached, but resigned before his inevitable impeachment in heavily Democratic Party-dominated Congress. In the Clinton story, it should be noted that even a Republican majority Senate failed to convict and remove him from office in 1999.

What the Democrats do have in their favor are a number of GOP Senators like John McCain and Bob Corker who seem to be leaning in the direction of a more robust investigation of the Trump administration's behavior.

But the Democrats' calls for either a special prosecutor or an independent counsel to probe the White House further are being sold the wrong way, with innuendo about larger conspiracies than even a Trump foe like McCain could support.

As we learned during the Clinton scandal, Independent Counsel Kenneth Starr simply went on a four-year-long fishing expedition that started with an Arkansas land deal and finally struck gold with the Monica Lewinsky affair.

Republicans are not going to support that kind of sustained witch hunt. Democrats ought to realize that their doomsday rhetoric about Donald Trump hasn't changed since the election, making every subsequent repetition of those words that much more worthless. In fact, many leading liberals and Democrats were calling for impeachment even before President Trump took office.

Instead of running for the cameras and microphones every time an unfavorable news report about President Trump hits the airwaves, Democrats should be hitting the phones and calling a few leading Republicans to work out some way they can band together to call for a comprehensive formal investigation.

And they must do so in a way that will allow establishment Republicans to save face and not look like traitors. Until they do that, Democrats are making it all too easy for the potential Trump scandals to stray from any kind of fact-finding exercise and lapse into a binary partisan feud President Trump has an excellent chance of winning... again.

Commentary by Jake Novak, CNBC.com senior columnist. Follow him on Twitter @jakejakeny.

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