A new Pennsylvania poll is filled with bad news for Republicans

Key Points
  • Democrats have a lead on the generic congressional ballot in Pennsylvania and in the state's Senate race, according to a Muhlenberg College poll.
  • A plurality of respondents also disapprove of President Donald Trump and the Republican tax plan.
  • Pennsylvania is one of the most important states in determining which party controls the chambers of Congress after November's elections.
A man walks past a 'Stand Up For Steel, Stand Up For America' sign while arriving at the United States Steel Corp. Clairton Plant coke manufacturing facility as emissions rise in Clairton, Pennsylvania.
Andrew Harrer | Bloomberg | Getty Images

A new poll shows warning signs for Republicans in Pennsylvania, one of the states most critical to determining which party controls Congress after November's elections.

With just under seven months until the midterms, Democrats have strong advantages both on the generic congressional ballot in Pennsylvania and in the race to hold on to Democratic Sen. Bob Casey's seat, according to a Muhlenberg College poll. In addition, a majority disapproves of President Donald Trump, and a plurality disapproves of the Republican tax law.

Much can change in the months before the elections, and the GOP hopes public opinion of its tax plan can improve and boost the party's midterm hopes. The single poll also does not capture public opinion at the level of specific House districts.

Republicans in recent days have pointed to a shrinking lead for Democrats on the national generic ballot, including a Washington Post-ABC News poll that found only a 4 percentage point advantage for Democrats. They have also highlighted an NBC News/Wall Street Journal poll that found 35 percent of Americans think Republicans are better equipped to handle the economy, while only 28 percent said Democrats are more suited.

Still, the Pennsylvania survey depicts a challenging environment for Republicans in one of the most important states for their effort to hold on to congressional majorities.

Sen. Bob Casey (D-Pa.) walks on stage to deliver remarks on the first day of the Democratic National Convention at the Wells Fargo Center, July 25, 2016 in Philadelphia, Pennsylvania.
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Earlier this year, House Democrats got a boost when the Pennsylvania Supreme Court revised a GOP-drawn congressional map. Under the new map, which Republicans have argued is unconstitutional, nonpartisan election handicappers consider at least five seats currently held by Republicans competitive. GOP incumbents are retiring from multiple Pennsylvania seats.

"With the recent redistricting in Pennsylvania, the strong Democratic advantage in the generic ballot is particularly significant and troubling for the GOP," said Christopher Borick, a political science professor and director of the Muhlenberg College Institute of Public Opinion.

Rep. Charlie Dent, a moderate Republican from the state, had said he would retire after his term, but said Tuesday that he would resign in May. His resignation leaves open the possibility for a special election to fill his seat before November.

President Donald Trump won the state by less than 1 percentage point in the 2016 election, after former President Barack Obama carried it in both 2008 and 2012. Polls have suggested a shift toward Democrats in the swing state this year.

The National Republican Congressional Committee and Pennsylvania Republican Party did not immediately respond to requests to comment on the poll.

Here are some of the findings from the survey, which was taken between April 4 and April 12:

  • Forty-seven percent of voters surveyed said they would prefer a generic Democrat in their district, compared with 38 percent who would support a Republican. The GOP hopes to stop major Democratic gains in the state as it tries to prevent the minority party from winning the 23 Republican seats it needs to control the House.
  • Forty-eight percent of respondents said they would support Casey, while 32 percent said they would back Rep. Lou Barletta, the leading Republican candidate in the Senate race. Unseating Casey would help Republicans hold or expand their narrow 51-seat majority in the Senate. Barletta spokesman David Jackson said the campaign is "very confident that as Lou Barletta is introduced to voters all across Pennsylvania, the ballot test will continue to close until a Barletta victory in November."
  • Only 39 percent of voters surveyed said they approve of the job Trump has done, compared with a 55 percent majority who said they disapprove. Opinions on a president can often rub off on candidates from the same party.
  • Thirty-nine percent of respondents approve of the GOP tax law, compared with 46 percent who disapprove of it. Republicans have made the tax overhaul, their signature achievement during the first year of GOP control of Capitol Hill and the White House, a major selling point for the midterms. House Republican leaders believe voters will have a better opinion of the tax policy when they have more time to understand how it will affect their paychecks. National Republican Congressional Committee spokesman Jesse Hunt said that "tax reform is viewed positively in every competitive district in the country" and contended that a Republican rebound in the generic ballot is due to voters seeing the benefits of the tax plan.

The telephone poll surveyed 414 voters and has a margin of error of plus-or-minus 5.5 percentage points.

— Graphic by CNBC's John Schoen.

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