WASHINGTON – The midterm elections are all about the man who's not on the ballot.

A new USA TODAY/Suffolk University Poll finds President Donald Trump driving the decisions of a majority of voters who say they are determined to send a message of either support or opposition to him. That dynamic is giving Democrats an edge as the crucial campaign heads into the final stretch.

A majority of those surveyed say Trump will have "a lot" of influence on their congressional vote on Nov. 6 – 35 percent who are casting their ballot to show their opposition to him, 23 percent to show their support. Only one in four say the president doesn't have at least some effect on their vote.

Indeed, Trump hasn't shied from making the Nov. 6 election a referendum on him, holding huge rallies in a string of red and swing states and telling the crowds that a vote for the local Senate or House candidate is "a vote for me." Midterms are often a judgment about the sitting president, but never in modern times has one campaigned so hard to make sure it is.

That now translates to an advantage for Democrats on the generic congressional ballot – that is, the hypothetical choice between an unnamed Republican and an unnamed Democrat. By 51-43 percent, likely voters say they would support the Democratic candidate, not the Republican one, if the election were held today. That eight-point difference is a significant edge, albeit not an overwhelming one. In the USA TODAY poll in August, Democrats led by 11 points.

The telephone poll of 1,000 likely voters Thursday through Monday has a margin of error of plus or minus 3 percentage points.

"Trump basically disagrees with everything I stand for," said Ash Paulsen, 34, a producer and video-game journalist from Los Angeles who was among those surveyed. A political independent, he voted for Hillary Clinton in 2016. "My hope is that the Democrats will have taken back enough power that they can either halt or seriously kneecap the president's agenda."

Hanna Treece-Fawler, 44, a Republican from Hot Springs, Arkansas, who works in sales, said her support for Trump is one factor behind her vote, and she suspected that feeling may be more widespread than many are willing to acknowledge. "I believe that people secretly support him, but not in front of their family and friends," she said in a follow-up interview.

In the poll, 43 percent approve of the job Trump is doing as president; 54 percent disapprove, a bit better than his 40-56 percent approval-disapproval rating in the August survey. But the intensity of feeling runs against him nearly 2 to 1: 44 percent say they "strongly" disapprove while 24 percent "strongly" approve.

Different parties, different issues

Republicans and Democrats have different issues on their minds.

For Republicans, the top issue by far is immigration and border security, cited by almost one in five as the most important concern affecting their vote. The economy ranks second, and a collection of economic issues – taxes/the budget/the deficit – are third.

For Democrats, the first issue by far is health care, cited by 14 percent in response to the open-ended question. Civil rights/gender equality is second, followed by views of Trump.

And among independents, health care is the only dominant issue, named by 20 percent. No other concern broke into double digits for voters in the middle.

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The fierce divide over Trump could make it difficult to build bipartisan coalitions to pass legislation on any issue over the next two years. By more than 20 percentage points, 56-35 percent, voters say they want to elect a Congress that mostly stands up to Trump rather than one that mostly cooperates with him. There is a predictable partisan divide on that question, but notably independents by more than 4-1 prefer a Congress that stands up to the president, 69-16 percent.

House Democratic leader Nancy Pelosi of California in recent days has said, however, that a Democratic majority could investigate the Trump administration while also negotiating agreements on some policy priorities. In an interview with USA TODAY on Monday, Trump predicted he could do business with a Democratic-controlled House on an infrastructure initiative and other issues.

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Among voters, though, expectations of compromise over the next two years are low.

If Democrats win a majority in the House of Representatives, more than four in 10 voters, 42 percent, expect "more partisan gridlock, with nothing getting done." Another three in 10, 30 percent, say nothing will change; "it will be a continuation of the past two years." Just one in five, 20 percent, predict there will be more bipartisanship "because the two parties will have to share power."

"Our government was not designed to be easy for a single party to get what they want," said Alex Cain, 29, the product manager for a tech company in the San Francisco Bay Area. An independent who "leans" to the GOP, he didn't cast a ballot for a presidential candidate in 2016. "It was designed to be difficult to the benefit of the people. Honestly, I think it's too easy for Republicans to just do what they want, and even though I'd say I am a Republican, I also don't think it's wise for a single party to be in control of anything."

A majority do expect action on one front, predicting that a Democratic-controlled House will seriously consider impeaching the president. That 54-32 percent assessment crosses party lines; most Democrats and most Republicans predict it will happen.

But there is a yawning divide on whether it should happen, and a warning flag from independents. An overwhelming 69 percent of Democrats say Trump should be impeached. It's no surprise that a close-to-unanimous 95 percent of Republicans are opposed. But independents are split down the middle: 43 percent favor impeachment; 45 percent oppose it.

"I just think their energy and our tax dollars could be used in much better ways, even though I'm not a big fan of the president," said Mona Prater of Fulton, Missouri, a former state government employee who is now a consultant on social services. She is registered as a Democrat but considers herself an independent. "They would better spend their time enacting legislation and doing things that are better for the country and their own districts than something that will probably never happen anyway."

How will you feel?

Get ready for strong emotions on Election Night.

Among Republicans, 69 percent say they will be "delighted" if the GOP retains control of both houses of Congress; 35 percent would be "angry" if they don't. Those were the two strongest positive and negative options.

The temperature among Democrats is higher: 73 percent would be "delighted" if Democrats won control of one or both houses of Congress; 52 percent would be "angry" if they didn't.

Almost no one feels impassive about what's ahead. Among all voters, fewer than one in 10 say the outcome won't register much of a reaction from them, one way or the other.

"I feel like we have to do something that registers our disapproval of the current administration," said Ann Maxwell, 74, a retired professor and a Democrat from Las Cruces, New Mexico.

The president "wants the country to be the best it can be," countered Wayne Bishop, 77, a retiree from Greenwood, S.C. He is a Republican who voted for Trump in 2016 but says he's not "in love" with him. "The other guys, I honestly feel, are trying to destroy everything that we have versus Trump."