A new poll shows how tight the Missouri U.S. Senate race continues to be and offers hints of encouragement to both sides.

The NBC/Marist survey shows incumbent Democrat Claire McCaskill and Republican challenger Josh Hawley tied among likely voters with each receiving 47% support and only 5% undecided.  Among the larger group of registered voters, Hawley gets 47% to McCaskill’s 46%.

When the field is expanded to include the Libertarian and Green Party candidates, Japheth Campbell and Jo Crain respectively, McCaskill leads by four points among likely voters, 44%-to-40%, although the poll notes the advantage is still within the margin of error.  The survey didn’t account for the recent addition of independent candidate Craig O’Dear, who was certified for the ballot just over a week ago by the secretary of state.

In what could be reflective of a national trend within the Democratic Party, McCaskill holds a big edge in passion.  Sixty-eight percent of her supporters back her strongly versus 46 percent of Hawley’s backers.

But in what could be representative of the state’s Republican tilt, McCaskill is under water in her favorability rating, with 49% of likely voters having a negative view of her, versus 41% who view her positively.

By comparison, likely voters are evenly split over Hawley, 36% positive compared to 36% negative.  28 percent of those surveyed are unsure of Hawley or have never heard of him.  He’s a first-time public office-holder, having been elected the state’s attorney general in 2016.

Lee Miringoff, director of the Marist College Institute for Public Opinion, which conducted this poll, thinks the race will hinge on voters’ view of Hawley once they become more familiar with him.  “Hawley is less well known, and the determining factor in this race is what happens when Hawley becomes better known,” Miringoff said.

University of Missouri at Columbia Political Science Professor Peverill Squire thinks the large sums of cash being directed at the race means both Republican and Democrat operatives think it’s winnable.  “Given how much money both sides are pouring into this race, that’s certainly the insiders’ thinking that it’s going to be a close race, and that they’re going to spend money here because they think they might be able to nudge the results in their direction,” said Squire.

McCaskill has complained that $70 million or more in outside money will be spent on the contest, acknowledging that some of it will be meant to boost her chances.  So far, outside organizations Americans for Prosperity (AFP) and National Republican Senate Committee (NRSC) have placed multimillion-dollar ads critical of McCaskill while the Senate Majority PAC has targeted Hawley.

The NBC/Marist poll reveals a possible problem area for Republicans in that support for President Trump seems to be wavering after he won the state by 19 points in 2016.

Forty-five percent of likely voters in the survey say they approve of President Trump’s job performance, while 46 percent disapprove.  And Trump’s favorability rating within the same group is 44 percent positive versus 50 percent negative.

In addition, a strong plurality of likely Missouri voters – 48 percent – say their vote for Congress in 2018 will be for Democrats to serve as a check and balance to Trump, versus 40 percent who say they’ll cast ballots intending for Republicans to help pass his agenda.

Professor Squire thinks the weaker Trump numbers are a problem because he’s been more popular in Missouri than in much of the rest of the country.  “If his support begins to slide here, that signals Republicans either have to move away from him or just bank on a hope that they can mobilize more of their voters than the Democrats can on election day,” Squire said.

Still, Republicans hold a 4-point advantage in congressional preference in the state, with 45 percent of likely voters wanting a GOP-controlled Congress and 41 percent preferring that Democrats be in charge.

According to the poll, Missourians are almost evenly split as far as which party they prefer to represent their congressional district, with 43 percent of likely voters choosing the Republican candidate, versus 42 percent who opted for the Democratic candidate.

The NBC/ Marist survey showed that healthcare and the economy are the top issues in the state.  25 percent of likely voters gave the nod to health care while 24 percent listed the economy and jobs. 10 percent said immigration was the most important issue while 9 percent singled out abortion and 8 percent said taxes and spending.  Among Democrats, the top issue was health care by a wide margin. For Republicans, it was the economy and jobs.

A large plurality of likely Missouri voters have a negative view of tariffs and barriers to trade.  45 percent said those tactics raise the cost of consumer goods and hurt the U.S. economy, versus 28 percent who said they protect jobs and help the economy.

The University of Missouri’s Professor Squire contends another issue has been overplayed in some circles.  He doesn’t think Senator McCaskill’s vote on Supreme Court nominee Brett Kavanaugh will impact her reelection chances, partly because he doesn’t think Kavanaugh is a popular choice.  “Nobody’s terribly enthusiastic,” said Squire.  “So, I don’t think it’s going to be a big political price to pay if any Democrats vote against Kavanaugh.  He’ll probably still make it through, but I don’t think it’s going to be a defining issue the way the Republicans might have hoped a few weeks ago.”

The NBC/Marist poll of Missouri was conducted August 25-28 and included 774 registered voters with a margin of error of plus-or-minus 4.2 percentage points.  It included 568 likely voters, yielding a margin of error of plus-or-minus 4.8 percentage points.