Our days are numbered. According to the Pew Research Center, after about five decades of demographic dominance, sometime in 2019 the millennials will pass the baby boomers in population.

Congratulation kids, and sorry about leaving you a world undergoing climatic disruption, the burden of unsustainable state and federal government debt and those college loans. Maybe if boomers had smartphones back in the day we would have figured this stuff out.

The boomers are defined as having been born between 1946-1964, meaning they range in age from about 54-72. That includes me, a 1956 baby. Dads came back from World War II, the American middle class expanded, the economy took off and people had lots of babies. Boom!

But we’re starting to die off. According to Pew, boomers peaked in 1999, reaching 78.8 million. This year we will slip to about 72 million. By 2050 boomers are projected to dwindle to about 16.6 million of us convalescing in nursing homes and populating elderly communities. If I make age 94, it sounds lonely.

Millennials, a group that includes my three sons (boomers remember that TV series), were born between 1981-1996, meaning they range in age from 22 to 38. According to Pew, this generation will hit 73 million sometime this year, a number aided by the immigration of young people in their age group.

Then there is Generation X. Born between 1965-1980 during a pause in American fertility, Generation Xers are sandwiched between their two larger generational cohorts. They peaked at 65.8 million last year, according to the Census Bureau. Politically and culturally, Gen X aligns more with millennials than boomers.

Any assessment of a generation has to be painted with the broadest of strokes, but that won’t stop me.

Boomers, raised during the golden era of America’s middle class, found themselves on one side of a generational divide with their parents over civil and women’s rights, the Vietnam War, music and drugs. Attending college in higher numbers, boomers concluded they had it all figured out. They were more political and idealistic than the generations that preceded and would follow.

They then went from fighting their parents to being protective (some would say overprotective) parents themselves, prizing organized activities for their children over the self-organized play that they had experienced. Parental encouragement displaced my way or the highway.

Millennials experienced a different America. Dad and mom worked. The attacks of 9/11, mass shootings and an economic collapse were traumatic, breeding skepticism if not cynicism. They have delayed marriage and having kids. Many embrace the diversity and entertainment opportunities cities offer, leaving suburbs to age.

If there is a gap, it’s technological. Millennials are the first generation comfortably immersed in a digital world and the last that will have memories of what it was like before.

But, as noted, they have not been as political as their parents or grandparents. In the 2016 election, only 51 percent of eligible millennials voted, compared to 63 percent of Gen Xers and 70 percent of older voters.

It appears the millennial generation may have begun to awake politically in the 2018 midterm election, however, and that’s not good news for Republicans. It is a generation that is more racially diverse, takes reproductive rights as a given, is extremely tolerant on cultural issues such as same-sex marriage and is far less religious. None of that lines up with 21st century Republicanism.

No surprise then that Pew found 55 percent of millennials identified as Democrats or Democratic-leaning independents, while just 33 percent identified as Republicans or Republican-leaning independents.

Failing to have a message that resonates with the new generational top dog is not a good long-term strategy for the Grand Old — and getting older — Party.

Paul Choiniere is the editorial page editor.