The battle lines are being drawn five months ahead of the midterms, with more Americans than at any point in at least the last two decades saying they're enthusiastic about voting — and record numbers of voters say President Trump and which party controls Congress are big factors in their vote, according to a new Pew Research Center survey released Wednesday.

Voters also are saying they want candidates to talk more about immigration and health care, two hot-button issues that have no simple solutions or easily navigable middle grounds.

Just Wednesday, the president backed down from his "zero tolerance" immigration policy that has resulted in the separation of families, while adults who crossed the border illegally are held for adjudication. A long-term comprehensive solution, however, remains out of reach. On healthcare, Republicans have failed so far to "repeal and replace" the Affordable Care Act, but they did strip out the mandate to buy insurance, which policy experts warn could raise the prices of premiums in October, a month before this fall's elections.

Enthusiasm is at record levels

Overall, slightly more than half of Americans (51 percent) told Pew they are "more enthusiastic about voting than usual," the highest share saying so in at least the last 20 years since Pew has been asking the question.

Democrats are more enthusiastic than Republicans, but not by much — 55 percent of Democrats said they are more enthusiastic than usual, but 50 percent of GOP voters said the same. Those are both very high numbers overall for midterms.

Generally, in midterms, the party out of power is far more fired up. That's been the case in each of the last three midterms — which have all been wave elections resulting in control of at least one chamber of Congress changing hands.

In 2006, when Democrats benefited from the spiraling Iraq war and President George W. Bush's declining approval numbers to take control of Congress, a slightly lower number of Democrats than today said they were more enthusiastic than usual (47 percent). But they far outnumbered Republicans in who said they were more enthusiastic in 2006 (30 percent), a 17-point advantage.

In 2010, when Republicans won a whopping 63 seats in the House and regained control of that chamber, the GOP was ahead on this question by 13 points (55 to 42 percent). And in 2014, when Republicans won back the Senate, they had an 8-point overall advantage (45 to 37 percent).

So the bottom line is Democrats today are as enthusiastic about voting as Republicans were in 2010, but Republicans are also fired up, which could mitigate GOP losses in the House and help them protect their slim Senate majority.

Both parties also see who controls Congress as consequential, with a record 68 percent saying so. That number has been steadily on the rise in the past two decades, evidence that elections have become far more nationalized since the Bill Clinton impeachment and through Bush v. Gore, 9/11, the Iraq war, Obamacare and Trump. Politics just isn't so local anymore.

Democrats need to win nearly two dozen seats to take control of the House. They are facing a very difficult map in the Senate, defending seats in 26 states, many of which Trump won handily in 2016. Republicans are defending just nine Senate seats.

The double-edged Trump sword

Three-fifths of Americans (60 percent) said that their vote is essentially a vote for or against the president. That is the highest percentage of voters saying that in at least three decades, Pew found.

What's more, a strong majority of Democrats (61 percent) see their vote as one against Trump and a majority of Republicans (52 percent) see it as one for him.

Putting those numbers in context again shows Republicans' support for Trump to be pretty strong. Consider that that 52 percent seeing their vote as one for Trump is nearly 20 points higher than the percentage of the GOP who saw their vote as one for Bush in 2006 and is also higher than the percentage of Democrats who said their votes in 2010 and 2014 were to support Obama. That could further insulate Republicans from massive losses this year.

Roiling all of this is a strong anti-incumbent sentiment. Two-thirds of Americans say they do not want to see most representatives elected.

Majorities are concerned about how either party will deal with Trump after the election — 58 percent of voters think Democrats will spend too much time investigating Trump if they win, and an equal but different 58 percent think Republicans would not focus enough on oversight of the Trump administration.

On the issues

If it's the economy, stupid, Republicans are in pretty good shape this fall.

Pew found Democrats have advantages, sometimes sweeping, on almost all issues — but not on dealing with the economy.

Republicans maintain an advantage over Democrats on doing a better job dealing with a terrorist threat and the economy. They also have smaller advantages on dealing with the budget deficit, taxes and trade, but they have relinquished their advantages on dealing with gun policy, immigration and health care.

Americans also say they prefer Democrats to deal with foreign policy, drug addiction (something the president and the GOP have talked about a lot), abortion and contraception, race and ethnicity issues and the environment.

Still, the GOP advantage on the economy could be Democrats' biggest problem heading into the midterms. The country is in a time of relative peace and prosperity, with the lowest unemployment numbers since the turn of the century and Trump stepping off of a nuclear standoff with North Korea and putting on a show of diplomacy.

That could be why Democrats' advantage on the question of who Americans want to control Congress is only 5 points (48-to-43 percent) in this poll. Democratic strategists would feel far more comfortable with a larger lead on that question, as they had in past wave years.

