Photos: Jim Watson/AFP via Getty Images

Two striking symbols — the border wall and America's first Black president — did the campaigning yesterday for presidential candidates trying to turn out bases that are worlds apart.

The state of play: Arizona, a state that President Trump won handily in 2016 but where polls now show Joe Biden leading, was firmly on both men's minds.

Trump visited Arizona for a photo-op at his "unclimbable" border wall. Trump decried "agitators" who tear down monuments.

  • At a church in Phoenix, he addressed a massive, mask-free gathering of young supporters at an indoor hall, telling them: "The left is not trying to promote justice or equality or lift up the downtrodden."

President Obama joined a Biden campaign event for the first time — a virtual fundraiser that instantly became the campaign's biggest single haul, with 175,000 guests and $7.6 million in donations.

  • Without naming either man, Obama said that his Republican predecessor George W. Bush had "a basic regard for the rule of law and the importance of our institutions" and that "there was still a sense of a shared American idea that we could build on." By contrast, he suggested Trump and his enablers have "gone at the very foundations of who we are and who we should be."
  • Obama spoke of a "great awakening" of young people who are inspired to correct centuries of injustice, and suggested a vote for Biden was less about partisanship than patriotism.

Biden campaign manager Jen O'Malley Dillon told supporters that Biden now sees Arizona, along with two redder states, Texas and Georgia, as being within the margin of error and target-worthy. 

  • Obama is expected to do several events with Biden throughout the campaign, not just fundraisers. But his presence also gives Trump an opportunity to replay some of his greatest hits and gripes against Obama and attack everything Trump says the old administration did wrong — ultimately trying to marry Biden to that image for voters.

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