WASHINGTON — Six weeks before the 2018 midterm elections, Democrats hold a 12-point lead in congressional preference among registered voters, with nearly six-in-10 saying they’d like to see significant change in the direction President Donald Trump has been leading the country, according to a new national NBC News/Wall Street Journal poll.

The results suggest a political environment where Democrats have the clear advantage in their pursuit to win back control of Congress in November.

“Americans are hitting the brake in a midterm, and trying to send the signal that they’re not satisfied,” said Republican pollster Bill McInturff, who conducted the survey with Democratic pollsters at Hart Research Associates.

“The public is clearly saying, once again, they want to shake up the status quo,” added Democratic pollster Fred Yang.

Still, the same poll shows that Republican enthusiasm about the upcoming election has increased, drawing nearly even with Democrats; that GOP attacks on immigration and Democratic House leader Nancy Pelosi are potent in individual races; and that nearly 70 percent of voters are satisfied with the economy.

In the survey, which was conducted Sept. 16-19, 52 percent of registered voters say they prefer a Democratic-controlled Congress, versus 40 percent who want the Republicans in charge.

That 12-point lead for Democrats — their highest of the cycle in the poll — is an increase from August, when they held an 8-point edge, 50 percent to 42 percent, although the change is within the survey’s margin of error.

Among the voters who are most likely to vote — the first time the NBC/WSJ poll has measured these voters for the 2018 elections — the Democrats’ advantage falls to 8 points, 51 percent to 43 percent.

In the larger pool of registered voters, McInturff points to warning signs for Republicans. They trail Democrats among moderates and independents by more than 30 points; they’re losing women ages 50 and older by nearly 20 points; and they’re behind among voters living in competitive congressional districts by 12 points, 53 percent to 41 percent.

Additionally, a combined 59 percent of voters say they’d like to see either “a great deal of change” or “quite a bit of change” in the direction Trump has been leading the country.

That includes 61 percent of independents and even a third of Republican respondents.

And by a 42 percent-to-31 percent margin, voters say their message in November will be for more Democrats to serve as a check and balance to Trump and the congressional Republicans, instead of Republicans who will help Trump and the GOP pass their agenda.

President Trump’s job rating in the poll stands at 44 percent approve, 52 percent disapprove — essentially unchanged from August’s poll.

GOP catches up in enthusiasm

The good news for Republicans in the NBC/WSJ poll is that they’ve caught up to Democrats on enthusiasm about the upcoming midterm elections.

Sixty-five percent of registered Democrats say they’re very interested in the midterms — registering either a “9” or “10” on a 10-point scale — compared with 61 percent of Republicans who say the same thing.

That narrow 4-point advantage for Democrats is down from their leads of 11 points in August (63 percent to 52 percent) and 16 points in July (65 percent to 49 percent).

The groups with the highest level of interest in the election: Seniors (73 percent register either a “9” or “10), Democrats (65 percent), whites (61 percent), Republicans (61 percent) and African Americans (53 percent).

The groups with the lowest level of interest: Independents (37 percent) and those ages 18-34 (35 percent).

The most and least popular issue positions in 2018

The NBC/WSJ poll also asked voters positions on key issues in the 2018 campaign.

The most popular issues:

58 percent said they are more likely to vote for a congressional candidate who favors allowing young adults who were brought into the country illegally by their parents to stay in the U.S. legally to attend college or to work;

55 percent said they are more likely to vote for a candidate who supports cutting the tax rate for businesses and corporations — and cutting taxes for most Americans;

51 percent said they are more likely to vote for a candidate who favors stricter regulations on assault and military-style firearms;

And 47 percent said they are more likely to vote for a candidate who favors “Medicare For All” — a single-payer health-care system in which all Americans would get their health insurance from one government plan.

The least popular issues:

82 percent said they are less likely to vote for a candidate who favors cutting Social Security and Medicare to help pay for Trump’s tax cuts;

55 percent said they are less likely to vote for a candidate who favors increasing funding for a wall along the U.S.-Mexico border;

53 percent said they are less likely to back a candidate who supports Trump’s issue positions over 90 percent of the time.

52 percent said they are less likely to vote for a candidate who supports weakening or eliminating the Affordable Care Act, also called Obamacare;

48 percent said they are less likely to vote for a candidate who favors abolishing ICE, the agency in charge of immigration and customs enforcement;

And 44 percent said they are less likely to vote for a candidate who supports Nancy Pelosi as the next speaker of the U.S. House of Representatives if Democrats take control of Congress.

Sixty-nine percent say they’re satisfied with U.S. economy

Finally, the NBC/WSJ poll finds 69 percent of American voters saying they’re either “very” or “somewhat” satisfied with the state of the U.S. economy — tied for the highest percentage on this question since 2001.

The all-time high, however, was in September 1998, before President Bill Clinton and Democrats picked up seats that midterm cycle, when a whopping 86 percent of all adults said they were satisfied with the economy.

And when asked if Trump’s policies have helped or hurt the economy, 41 percent said helped and 26 percent said hurt. Thirty percent said they haven’t made much of a difference.

The NBC/WSJ poll was conducted September 16-19 of 900 voters — nearly half reached by cellphone — and it has an overall margin of error of plus-minus 3.3 percentage points. The margin of error for the 594 likely voters is plus-minus 4.0 percentage points.