That is why Republicans could have a harder time than they think pinning labels such as “socialist” and “radical” to the candidates who support these proposals.

The Green New Deal? It’s a 14-page nonbinding resolution calling on Congress to spend the next decade finding ways to reduce carbon in the atmosphere. Six senators who are running for the Democratic presidential nomination or thinking about it have signed on as co-sponsors.

The bill sets an ambitious target: “net-zero emissions by 2050.” What it does not contain are some of the extreme ideas that Republicans have mocked, such as getting rid of air travel and flatulent cattle, both of which were contained in a document that the office of Rep. Alexandria Ocasio-Cortez (D-N.Y.) put out and has since disavowed.

Trump has called the Green New Deal a “high school term paper that got a low mark.” And Senate Majority Leader Mitch McConnell (R-Ky.) has talked about putting it to a vote on the Senate floor.

But Sen. Amy Klobuchar (D-Minn.) told Fox News’s Bret Baier that she views the Green New Deal as merely “aspirational. I see it as a jump-start. So I would vote yes [on the resolution], but if it got down to the nitty-gritty of an actual legislation, as opposed to, ‘Oh, here’s some goals we have,’ that would be different for me.”

One Democratic senator and potential presidential contender who has not endorsed the measure, Sherrod Brown of Ohio, insists that he, too, supports an aggressive effort to combat climate change. But he is no more explicit about what he would offer as an alternative: “I’m not going to get in the position of every time somebody has a really good idea or a big idea that I have to talk in great detail about my position on it.”

Medicare-for-all gets 81 percent support from Democrats in a recent survey by the Kaiser Family Foundation.

Four senators already running have jumped aboard the Medicare-for-all legislation that Sen. Bernie Sanders (I-Vt.) introduced in 2017. But most remain leery of committing to details and trade-offs. Among them, only Kamala D. Harris (D-Calif.) favors Sanders’s hard-line proposal to get rid of the private insurance system in favor of having all Americans enroll in government-financed health coverage.

Sen. Elizabeth Warren (D-Mass.) told Bloomberg Television her ultimate goal is to “make sure that everybody gets coverage at the lowest possible cost to all of us,” but she emphasized that there are “lots of paths for how to do that.” Warren noted that she also supports legislation that would retain private coverage, while giving people an option of buying into Medicaid.

Sen. Cory Booker (D-N.J.), also on record as a co-sponsor of Medicare-for-all legislation, has said flatly that he would oppose getting rid of private insurance and he wants to see more incremental expansion of government health programs.

The presidential contenders are not sweating the policy details because they understand that Democratic primary voters aren’t, either.

The Green New Deal and Medicare-for-all are popular in the party, but they are not litmus tests. A Monmouth University poll in late January asked registered Democrats and Democratic-leaning independents whether they would be more likely to support a presidential candidate who agreed with them on most issues but who would have a hard time defeating Trump, or one who disagrees on most issues but would have a better chance to beat the president.

It wasn’t even close. While 33 percent said they would choose a candidate based on his or her policies, 56 percent answered that they would go with the most electable one.

“The bulk of the messaging is going to converge,” South Bend, Ind., Mayor Pete Buttigieg, who is also running for president, told me. “It’s going to come down to who they think is the most compelling in delivering the message.”

So are we in for a Democratic primary that is devoid of substance? Not likely. All of the candidates will be pressed to commit to more specifics when they start facing one another on the crowded debate stage, beginning in June.

With their big and aspirational slogans, however, Democratic candidates are signaling from the start that they are united behind a clear set of priorities. And in leaving their options open on how they would achieve them, they are delivering another message — that they understand it will take pragmatism and flexibility to govern.