Has Michael Bloomberg begun the battle for 2020?

Did former New York Mayor Michael Bloomberg just take a page out of the playbook of Sen. Ed Muskie from half a century ago?

In his first off-year election in 1970, President Richard Nixon ran a tough attack campaign to hold the 52 House seats the GOP had added in ’66 and ’68, and to pick up a few more seats in the Senate.

In that campaign’s final hours, Muskie delivered a statesmanlike address from Cape Elizabeth, Maine, excoriating the “unprecedented volume” of “name-calling” and “deceptions” from the “highest offices in the land.”

Nixon picked up a pair of Senate seats, but Democrats gained a dozen House seats, and the press scored it as a victory for Muskie, who was vaulted into the lead position for the 1972 Democratic nomination.

In the final days of this election, Bloomberg just invested $5 million to air, twice nationally, a two-minute ad for the Democratic Party that features Bloomberg himself denouncing the “fear-mongering,” and “shouting and hysterics” coming out of Washington.

“We can be a nation of immigrants while also securing our borders,” the mayor said.

That $5 million ad buy was only Bloomberg’s latest contribution to the Democratic Party during an election campaign into which he had already plunged $110 million of his own money.

Contributions of this magnitude support the idea that Bloomberg will seek the presidential nomination as a Democrat.

Yet, Bloomberg is no Ed Muskie, who had been Hubert Humphrey’s running mate in 1968 and was widely regarded a top contender for 1972.

With the energy of the Democratic Party coming from militants, minorities and millennials, would these true believers rally to a 76-year-old Manhattan media magnate who wants to make their party more centrist and problem-solving, and to start beavering away at cutting the deficit?

Yet Bloomberg’s opening move may force the pace of the politics of 2020. Should he announce, and start spending on ads, he could force the hand of Vice President Joe Biden, who appears the Democrats’ strongest candidate in taking back Pennsylvania, and the states of the industrial Midwest, from Trump.

On the left wing of the Democratic Party, which seems certain to have a finalist in the run for the 2020 nomination, the competition is stiff and the pressure to move early equally great.

Nancy Pelosi is determined to become speaker again, while the Congressional Black Caucus has entered a demand for one of the two top positions in the House.

Millennials also want new leadership. And to many centrist Democrats in swing districts, Pelosi as the visible voice and face of the national party remains a perpetual problem.

Democrats have captured the House, but the rewards may be fleeting.

And should the economy, which has been running splendidly under a Republican Congress and president, start to sputter under a divided Congress there is no doubt that the Democratic House majority, with its anti-capitalist left and socialist ideology, would emerge as the primary suspect.

2019 is shaping up to be a year of gridlock on Capitol Hill. This could be the kind of battleground Donald Trump relishes.