President Joe Biden speaks at an event at the Milwaukee Department of Public Works in Milwaukee, Tuesday, Oct. 8, 2024, to discuss his administration's progress in replacing lead pipes in Wisconsin and across the country. (AP Photo/Susan Walsh)

BRYN MAWR, Pa. (AP) — President Joe Biden made a rare jump into the 2024 political battleground fray since taking a step back after ending his reelection bid.

He campaigned Tuesday in Pennsylvania for a close ally after having stopped in Wisconsin to spotlight a signature legislative achievement.

But as Biden made a quick swing through the key states, two Democratic senators locked in competitive reelection battles took markedly different approaches to the outgoing president, whose approval ratings in a significant swath of the country remain in the pits.

Biden was fully embraced by Democratic Sen. Bob Casey when participating in a private campaign fundraiser in suburban Philadelphia for the senior Pennsylvania senator. The event overlapped with the Philadelphia Phillies baseball playoff game against the New York Mets.

But in Milwaukee, where Biden spotlighted his administration’s efforts to replace the nation’s toxic lead pipes, incumbent Democratic Sen. Tammy Baldwin was conspicuously absent.

“Democrats in tight races, for the most part, are calculating that the risk of embracing Biden far exceeds any reward that his efforts would bring to their campaign,” said Christopher Borick, director of the Muhlenberg College Institute of Public Opinion in Pennsylvania. “There just aren’t many places where he can be of much help to Democrats in competitive races.”

Biden has spent scant time on the campaign trail since ending his reelection effort in July. That makes his stops in Pennsylvania and Wisconsin — two tightly contested states that Vice President Kamala Harris and former President Donald Trump see as crucial — all the more notable.

Casey's and Baldwin's races are also seen as must-wins for Democrats who are trying to maintain their razor-tight control of the Senate.

Biden, after dropping out, pledged to campaign hard for Harris and Democrats. But as the campaign season has played out, he's largely stayed on the sidelines as he remains a flawed surrogate for Harris and down-ballot Democrats.

Still, Democrats are thoroughly united in opposition to Trump, and Biden lambasted his predecessor at both appearances.

In Pennsylvania, Biden highlighted the revelations in the new Bob Woodward book “War” that Trump secretly sent COVID-19 tests to Russian President Vladimir Putin. Democrats have long suggested that Trump's seeming coziness with Putin is a national security risk.

“You see what came out today?" Biden said at the fundraiser. "So he calls his good friend Putin — not a joke — and makes sure he had the tests. He had the tests.”

Casey, running against Republican David McCormick as he seeks a fourth Senate term, has a long-running relationship with Biden and grew up on the same street in Scranton as the president.

Biden noted that he shares “Scranton” values with Casey, whereas Trump has “Mar-a-Lago” values, a reference to the former president's resort and residence in Florida.

Still, Biden, 81, faces considerable skepticism inside a state that — along with Delaware — he considers to be his own. About 4 in 10 Pennsylvania voters had a favorable view of Biden and about 6 in 10 had an unfavorable view, according to a Monmouth University poll published in late September.

In Wisconsin, Baldwin was spending Tuesday on the other side of the state from Biden, attending campaign events and getting an award, according to her campaign and Senate office.

“Senator Baldwin had a previously scheduled event at a family farm in Eau Claire to receive the American Farm Bureau Federation’s ‘Friend of Farm Bureau’ award recognizing her leadership fighting for America’s hardworking farmers, growers, and producers," said Eli Rosen, Baldwin's communications director, in response to a query about why she was skipping the president's visit.

Biden’s favorability in Wisconsin has hovered around 40% for the past year and did not increase after he dropped out of the presidential race this summer, according to a recent Marquette University Law School poll.

Baldwin, who is seeking her third term, is facing Republican Eric Hovde, the CEO of a Wisconsin real estate development company.

She skipped four of Biden’s five appearances in the state this year, but she has appeared with Harris, including speaking to a crowd of more than 10,000 people last month in Madison.

“Baldwin may be able to skip a Biden event, but she cannot avoid the verdict of working families in Wisconsin when they head to the polls,” said Wisconsin GOP chairman Brian Schimming.

Biden's visit to Wisconsin, which has some 340,000 lead pipes, came as the Environmental Protection Agency on Tuesday issued a final rule requiring drinking water systems across the country to identify and replace lead pipes within 10 years.

Biden's 2021 infrastructure law provides $15 billion to find and replace the toxic pipes, a legacy the Biden White House says will have an impact on generations to come. Lead can lower IQ and create behavioral problems in children, and the administration believes the legislation will go a long way in removing some 9.2 million lead pipes carrying water to U.S. homes.

Biden used his speech in Milwaukee to take digs at Trump and Sen. Ron Johnson, R-Wis., who voted against the infrastructure law. Going back to a stock line, Biden noted that Trump routinely had “infrastructure week” during his own presidency but “he didn't build a damn thing.”

The president's appearance was also a touch wistful as Milwaukee County Executive David Crowley and Wisconsin Gov. Tony Evers lavished praise on Biden for being a strong partner for Milwaukee, a place Trump once called a “horrible city.”

Democratic U.S. Rep. Mark Pocan, whose district includes Wisconsin’s deeply Democratic capital city of Madison, said Biden’s policies are popular in the battleground state even if polls show he is not. Pocan, who is not in a competitive race, also defended Baldwin not appearing with Biden.

“If you’re in a competitive race, you have your calendar,” he said. “You have a strategy based on where you’re trying to get votes and you don’t change it when you have a surrogate come.”

Next week, Biden’s wife, Jill, is scheduled to campaign for Harris in Madison as part of a five-day effort by the first lady through the battleground states of Arizona, Nevada, Michigan, Wisconsin and Pennsylvania, Harris' campaign and the White House announced Tuesday.

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Bauer reported from Madison, Wisconsin. Associated Press writers Linley Sanders and Matthew Daly in Washington contributed to this report.

News from © The Associated Press, 2024