A plurality of voters in the key swing states of Michigan, Minnesota and Wisconsin said they would prefer to see Democrats take back control of Congress in the November election, a new poll finds.

A majority of voters in those states also said they disapprove of President Donald Trump’s job performance. But a plurality in each state think he deserves at least some credit for an improving economy, according to the latest NBCNews Marist poll.

Voters overwhelmingly agree on one issue: More than 90 percent of registered voters in each of the three states think the midterm congressional election will be “very important” or “important.”

If the election were held today, Michigan voters said they would choose a Democrat over a Republican by a 49-to-36 percent margin. Minnesota voters split 48-37 percent in favor of Democrats. Wisconsin voters said they prefer a Democrat in Congress by a 51 to 38 percent margin.

The three states are expect to be pivotal in the battle between Republicans and Democrats for control of Congress. With all 435 House seats up for re-election, Democrats need to flip 24 seats to win control. In the Senate, Democrats need to see a net gain of two of the 35 seats in play this November.

A majority in all three states also said they believe their vote in November will send a message that the country needs “more Democrats to be a check and balance to Donald Trump.” About a third of voters said their vote would be a message that more Republicans are needed to “help Donald Trump pass his agenda.”

On the subject of special counsel Robert Mueller’s investigation into Russian interference in the 2016 election, a majority of voters said they believe it is “a fair investigation. Less than a third characterized it as “a witch hunt.”