In Washington, power is fleeting. Elected and appointed officials know they better use it before they lose it.

In the House of Representatives, Republicans are going to lose it Jan. 3 when they become the minority party. The change in power that GOP representatives will experience will be dramatic – like Superman turning into Clark Kent or Wonder Woman turning into Diana Prince.

Voters elected a Democratic majority to the House in the Nov. 6 midterm elections, ending uninterrupted Republican control of the chamber that last began in 2011. With a few races still undecided, Democrats have flipped at least 35 seats held by Republicans. This gives the Democrats the ability to elect a new speaker of the House and install Democratic chairs to head every committee.

While the Senate will remain under Republican control in January, legislation needs to be approved in both the Senate and House to become law. So Republicans have only a short time left to pass bills during their lame duck session and get them to President Trump so he can sign them.

This task is more complicated than it sounds, because Republicans have plenty of disagreements with each other. But they would be foolish to let their differences prevent them from making progress on important measures in the next few weeks.

Republicans need to play chess and not Russian roulette with the Democrats. There is an opportunity to horse trade or to jam Democrats if Republicans adopt the ancient advice that “united we stand, divided we fall” and think strategically.

I urge Republicans to work long days and into the night for the remainder of this year to pass as many measures as they can, not kicking the can down the road to the next Congress where Democrats will be empowered.

House Minority Leader Nancy Pelosi, D-Calif., may need Republican votes to be elected speaker of the House, because some Democratic insurgents are saying they won’t support her bid.

The Democratic rebels are giving Republicans leverage over Pelosi to demand that she agree to some GOP priorities – like funding for a wall along the U.S.-Mexico border, as well as other spending measures – in return for their support.

The idea is that it is better to deal with the devil you know than what could come next.

I urge Republicans to work long days and into the night for the remainder of this year to pass as many measures as they can, not kicking the can down the road to the next Congress where Democrats will be empowered.

Republicans should be able to get bipartisan support for measures like a budget resolution needed to avoid a government shutdown, permanent repeal of the medical device tax, and a multibillion-dollar program to fund infrastructure expansion and improvement projects.

Then there are heavier lifts like immigration reform, border wall funding, tax cut 2.0 to target the middle class, and the Holy Grail – a full and complete repeal and replacement of ObamaCare.

Republicans should not squander the opportunity to lead – the sand is almost through the hourglass. For many representatives who lost their seats in the midterm elections, action and results could be a great legacy as they exit stage right.

Republicans should have no regrets as this year ends and not give up the fight in 2019. Democrats cannot govern alone next year.

If Democrats act in good faith and heed the electorate that is sick and tired of bitter partisanship they will get things done. Democrats would be wise to resist the temptation to get even for past grievances and the urge to engage in endless, pointless and fruitless investigations.

What Democrats need to realize and accept is that President Trump is transactional – not an entrenched ideologue. He wants to make deals and say he is winning, but on the other hand he will not be taken advantage of.

So the choice is clear. Republicans need to lead in the lame-duck session and Democrats need to help where they can or get out of the way.

Then when a new Congress arrives in January, Democrats need to reach across the aisle to advance legislation for the good of the country.

Democrats should remember that when President Clinton and President Obama suffered heavy midterm loses they still managed to get re-elected, in part because of the behavior of the opposition party and the way Republicans obstructed instead of governed.

Many Democrats in Congress have tied themselves to the delusional and obsessive anti-Trump “resistance” movement. They need to remember that they weren’t elected to come to Washington to stage protests and reflexively oppose everything the president and GOP lawmakers propose.

This is especially true for some of the young and far-left Democrats who call themselves democratic socialists and who support massive increases in government spending to fund a laundry list of expensive government programs. Voting for these measures means voting for big tax increases or unsustainable deficits that are likely to anger voters in 2020.

I believe President Trump can lead Republicans to compromise with Democrats in the House and Senate for the remainder of this year and in 2019, but it will take three to tango – the House, Senate and White House.

The lame-duck session should operate under the motto of “Lead or get out of the way.” The 2019 congressional session should operate under the motto of “Let’s make a deal.”

And Republicans who Pelosi turns to for support should ask: “What’s in it for us?”