Early on the morning after the midterm elections, a stunning new development that few Michigan political observers imagined possible took shape: Democrats, for the first time in nearly 40 years, took control of the vital swing state’s senate and house.

They achieved it in a year Republicans were expected to maintain their iron grip on the state legislature, but when the dust settled, Democrats held a 56-54 majority in the house and 20-18 advantage in the senate. It came in addition to Dems sweeping the statewide offices at the top of the ballot, retaining control of the state supreme court and winning a majority of US House seats.

“Michigan Republicans were decimated in an election when history tells us it never should have happened,” the right-leaning state political commentator Bill Ballenger wrote of the results. “The [Michigan] GOP lost everything of value.”

The bellwether swing state in America’s industrial upper midwest is a political prize that has voted for the presidential winner in the last four national elections, but despite its bipartisan tendencies, gerrymandered legislative districts drawn by Republicans for decades have virtually ensured Democrats rarely have a chance to govern at the state level here.

In the midterms’ wake, the confluence of forces that came together to propel the Democratic victory are becoming clear. Like elsewhere in the nation where Democrats performed well, the Michigan party benefited from facing many weak, extreme Republican candidates and a base motivated by the US supreme court overturning Roe v Wade.

But state Democrats also charted their own destiny in some ways, observers note. They spent more on state legislative races than in past years, ran popular statewide candidates at the top of the ballot, and passed a string of citizen-led progressive ballot initiatives over the last three cycles that paid off in 2022.

That started with the 2018 passage of initiatives for an independent redistricting commission and expansion of voting rights. The commission’s new lines went into effect this year, giving Democrats a much fairer shot at control. Meanwhile, the Democratic floor leader, Yousef Rabhi, who did not run for re-election but campaigned statewide for his party, spent most of election day at a university campus where hundreds of young people signed up to vote last minute. Their votes would not have been possible before the 2018 voting rights expansion.

In 2022, an initiative to codify abortion rights in the state and a further expansion of voting rights again energized the liberal base and boosted turnout, and this time they voted on races run in fairer districts.

“It was incredible to see,” Rabhi said. “But it was a multi-election process that never would have been possible prior to passing those laws in 2018.”

State pollster Ed Sarpolous of Target Insyght laid today’s fairer legislative lines over the results from the past 20 years and found that with those districts in place Democrats would have won control of the legislature in 2006 and 2008.

Pre-election polling by the Epic-MRA pollster Bernie Porn also highlighted how this year’s abortion rights initiative benefited Dems. Asked what single issue was motivating them to vote, 43% of respondents said abortion, which topped inflation by about 14 points.

“Abortion, abortion, abortion,” Porn said. “This proposal drove women and younger voters to the polls … and if Democrats in other states have a mechanism to put an abortion ballot proposal on the ballot in 2024, then they should consider that.”

The initiative, which passed by a 57-43 margin, also helped energize other key Michigan constituencies, like independents and Catholics, the latter of which have traditionally voted blue and are split on abortion, Sarpolous said.

“Democrats do well when there are issues that all voters care about and this was viewed not as an abortion issue, but a women’s rights issue,” he added.

Democrats in the legislature further benefited from what pollsters called the “coattails” effect. At the top of the ballot, Governor Gretchen Whitmer, the secretary of state, Jocelyn Benson, and attorney general, Dana Nessel, won their respective races by between eight and 15 points, which helped power Democratic candidates down ballot. Meanwhile, competitive races in US House seats had a similar effect, observers say.

They were helped by what Ballanger told the Guardian were “historically weak” Republican candidates for statewide office – each was a Trump-backed election denier who was viewed as an extremist. Whitmer and national Democrats far outspent Republican gubernatorial nominee Tudor Dixon and national Republicans, who may have given up on Dixon before the campaign ever got started.

An analysis by Sarpolous found 27,000 Republicans voted for Whitmer, while about 216,000 Republican-leaning independents stayed home.

“That was a killer,” Ballenger said. “That just affected races down the ballot.”

Rabhi echoed that, and said he heard anecdotally from voters around the state while campaigning that the election denialism in particular was a turn-off: “They are batshit crazy at this point and that’s what I heard from Republicans, Democrats and independents alike.”

He and other Democrats touted the strength of their legislative candidates who, along with Whitmer, focused on abortion and local issues that affected people in their districts. Republicans, by contrast, spent a large amount of resources on re-litigating the 2020 election, supporting gun rights or tying candidates to Joe Biden and inflation, a tactic that some say failed as Biden’s approval rating ticked up in the second half of the year.

“Democratic candidates were actually trying to listen to the concerns of voters rather than throw red meat at them with some of these issues that Tudor Dixon and other Republicans pursued,” said Rodericka Applewhite, Michigan Democrats’ senior communications adviser.

If they are to repeat in 2024, Democrats need to pursue the legislation they have been proposing in recent years that Republicans have killed, Rabhi said. That could mean repealing right-to-work, killing the GOP’s unpopular Line 5 gas pipeline being built through the Great Lakes, new oversight of unpopular utilities like DTE Energy, codifying equal rights for LGBTQ+ residents and more.

“Now that we have the majority we have to deliver on promises and be the bold progressives that we should be,” Rabhi said.