Vice President Harris is finding new support in the three Rust Belt states that helped deliver President Trump’s 2016 victory.

On issues like the economy and immigration, the two are now essentially tied in polling on who would do a better job at dealing with such problems. 

According to a new survey released Wednesday by Quinnipiac — which has been deemed one of the most accurate pollsters in the country — Ms. Harris is leading Trump, even if narrowly, in the states of Pennsylvania, Michigan, and Wisconsin. If she can win those three states, along with the others that are considered safely in her column, then she will be president come 2025. 

Ms. Harris leads Trump by six points in Pennsylvania, five points in Michigan, and one point in Wisconsin. The margin of error was 3.3 percent or less each in each of those states. 

Ms. Harris’s newfound strength in these key states can likely be attributed to her performance in last week’s presidential debate with Trump. Most polls found that viewers came away from the event thinking that the vice president had beaten her opponent. 

During that debate, she talked often about her “opportunity economy,” her promise to build more homes, and her pledge to sign a bipartisan immigration and border security law negotiated in the Senate earlier this year. That likely helped her close the gap with Trump on the questions of who voters believed would better handle the economy and immigration issues, which were two of Trump’s strongest points until President Biden dropped out of the race. 

In both Pennsylvania and Michigan, Trump has just a two-point lead over Ms. Harris on the question of who would be a better president for America’s economy. He has a four-point lead on that same question in Wisconsin. On immigration, by a margin of 50 percent to 48 percent, Pennsylvanians trust Trump more to handle the border and migrant issues. In Michigan, the margin for Trump being more trusted is just a point. In Wisconsin, Trump has a seven-point advantage on that question. 

“Three crucial swing states wave a red flag at the Trump campaign. The GOP’s most ‘go to’ attack strategies against Democrats on immigration and the economy may be losing momentum,” an analyst for Quinnipiac Polling, Tim Malloy, says. “Likely voters now see little daylight, in most cases, between Harris and Trump on who can best handle those key issues.”

In another sign of the vice president’s strength, Ms. Harris is drawing more support from registered Republicans than Trump is drawing from registered Democrats, while she is also winning among independents. 

In Pennsylvania, 7 percent of Republicans say they will vote for Ms. Harris while 4 percent of Democrats say they will support Trump. Among Michigan voters, 5 percent of Republicans said they would vote for Ms. Harris while zero Democrats said they would back Trump. Trump and Ms. Harris each take 4 percent from the other candidate’s party in Wisconsin. 

Similarly, the Republican and Democratic nominees are tied among independents in Wisconsin, each taking 46 percent, though Ms. Harris leads among the bloc in the other states. Ms. Harris leads Trump by 48 percent to 43 percent among Pennsylvania independents, and by 47 percent to 44 percent among Michigan independents.

For their favorability ratings, Trump is deep underwater in all three states while Ms. Harris is either slightly above or below water. He has a net negative favorable rating of nine points in both Michigan and Pennsylvania and a net negative rating of four points in Wisconsin. Ms. Harris has a net positive rating of three points in Michigan and one point in Pennsylvania, while having a net negative rating of two points in Wisconsin. 

The three Democratic Senate candidates in those Rust Belt states are running ahead of Ms. Harris in their own campaigns. Senator Casey — who is seeking a fourth term and is the son of a former Pennsylvania governor — is beating his Republican challenger Dave McCormick by nine points.

The Democratic nominee in Michigan, Congresswoman Elissa Slotkin, is beating her opponent, Congressman Mike Rogers, by five points. Senator Baldwin is ahead of the GOP nominee, Eric Hovde, by four points.