This has created tensions for Ms. Harris: Some voters say she has been “invisible” as vice president and are skeptical or even ignorant of her abilities and accomplishments, while some political strategists say she needs to differentiate her policy priorities from Mr. Biden’s so that she puts meat on the idea that she is “turning the page” on the past and is a change candidate.Ms. Harris has played a key role in the top achievements of the Biden-Harris administration to: cut health insurance and prescription drug costs; fight climate change; impose a minimum tax on multibillion-dollar corporations; crack down on wealthy tax cheats; fund free Covid vaccinations and treatments; send checks to most Americans and small businesses to help them deal with the pandemic; improve roads, bridges, mass transit.When a vice president running for president expands on the administration’s plans — like giving all first-time home buyers $25,000 in down payment assistance or increasing the tax deduction for start-ups from $5,000 to $50,000 — opponents ask why the vice president didn’t pursue the idea earlier. Mr. Trump and his campaign are leveling this attack against Ms. Harris today.