Starting with the Voting Rights Act of 1965, Democrats have a two generations-long commitment to ensuring that all Americans can vote. They believe “suppressing the vote” is always wrong, and you’d think the Democratic Party would consistently support the widest possible voter choice.

You would be wrong, however. It’s clear that, where primary elections are concerned, national Democratic organizations have no such qualms, and often stage-manage contests so their preferred candidate wins.

The Democratic Senatorial Campaign Committee ignited outrage among six female candidates in a Colorado Senate primary by endorsing former Gov. John Hickenlooper for the seat — one day after he abandoned his presidential bid. The DSCC emphasized Hickenlooper’s “electability,” and said it must start funding him immediately, the better to get the drop on incumbent Republican Cory Gardner.

This is, of course, many months before voters — as opposed to party professionals — have even started focusing on candidates. Why even have primary elections if parties try to determine the outcome before the races start?

The DSCC also placed its heavy thumb on the Maine Senate race featuring Republican Susan Collins, who is trying for an unprecedented fifth term. No Maine senator, not even her idol, Margaret Chase Smith, has served more than four.

Right out of the gate, the DSCC began funding Maine House Speaker Sara Gideon’s candidacy, and encouraging endorsements from national groups. It ignored at least one serious candidate, Betsy Sweet, who arguably has wider electoral experience than Gideon.

Gideon has never been chosen by voters beyond her House district, representing about 8,600 Mainers. Sweet finished third in the Democratic gubernatorial primary last year — won by Gov. Janet Mills — and impressed many with her appeal to first-time voters, as the only Democrat using public financing.

The frustrating thing for Democrats is that this ham-fisted effort to “pick winners” hasn’t worked. Democratic U.S. Senate Leader Chuck Schumer took over the campaign machinery in 2016, and, despite House gains in 2018, there are now fewer Democratic senators than when he started.

Could it be different? It could, and it has been. Roll the clock back three decades to when George Mitchell, then a little-known senator from Maine, led the DSCC effort for the 1986 election.

Mitchell emphasized candidate recruitment, issues and strategy — not, primarily, money or big names. He sensed an opening — six years after the Reagan landslide swept in a Republican Senate for the first time since 1952 — for Democrats to make gains, and succeeded, spectacularly, picking up eight seats and putting his party back in control.

Mitchell helped elect Democrats in such now unthinkable places as North Dakota and South Dakota, and ousted incumbents in Alabama, Georgia and North Carolina. Yet he never, ever, intervened in a contested primary.

A key example was Maryland, where Congresswoman Barbara Mikulski faced two better known male opponents, including a former governor. The DSCC stayed strictly neutral, but the day after Mikulski won the primary, it purchased ads in the crucial Washington, D.C., market, where she was almost unknown.

In November, Mikulski easily defeated a highly-touted Republican woman, and — though it’s now hard to believe — became the first Democratic woman elected a U.S. senator; she gave much of the credit to Mitchell. Two years later, Mitchell was majority leader, besting two better-known senators, Bennett Johnston and Daniel Inouye, to win the post.

Contrast that to 2016, when Schumer had similarly numerous opportunities, and flubbed almost all of them. Perhaps this difference in outlook, and effectiveness, stems from Schumer’s own undemocratic ascent to the second most powerful post in Washington.

Until 2004, when Democratic Leader Tom Daschle lost his seat, the race for caucus leader was regularly contested. That year, however, Harry Reid took the job without a fight — or so it appeared.

Schumer instead became the powerful conference chair, as the party split two leadership posts Lyndon Johnson had united in 1952, with one senator holding both the conference and leader positions. Schumer, the younger senator, made a deal to install Reid as leader — waiting his turn until Reid retired in 2016, when Schumer stepped up — again, uncontested.

There’s nothing that says senators must have a choice when they choose caucus leaders, yet it doesn’t bode well for democratic outcomes when they don’t.

Regardless of the DSCC’s machinations, there will be a Maine primary election next June, and voters will cast ballots. But the process has already been tainted, and that can’t be good for the party, or the country.

To its credit, the Maine Democratic State Committee in 2018 adopted a rule that no Democratic committee — state, county or municipal — can endorse in a contested primary. If only the national Democrats were listening, and taking seriously the principle enshrined in their name.

Douglas Rooks, a Maine editor, opinion writer and author for 34 years, has published books about George Mitchell, and the Maine Democratic Party. He welcomes comment at drooks@tds.net