How the White House hid troubling signs of Biden's aging 

As President Joe Biden, the oldest president in U.S. history, navigates his re-election bid, a complex picture emerges of a White House grappling with concerns about his age and mental acuity. For over a year, senior advisers have carefully managed Biden's schedule and public appearances, aiming to minimize signs of age-related decline.

The president's team has limited his daily itinerary, shielded him from impromptu exchanges, and restricted media appearances. They've twice declined Super Bowl halftime interviews and carefully scripted donor meetings. Travel suggestions have been dismissed due to stamina concerns, including a proposed weekly cross-country tour to promote the infrastructure law.

These efforts came to a head during last month's debate, where Biden's performance stunned party members and even some White House staffers. The event has become a turning point for many Democrats, including donors and lawmakers, who now express feeling misled about Biden's fitness for a second term.

High-profile supporters like Hollywood mogul Jeffrey Katzenberg have defended Biden's capabilities, citing personal interactions. However, some donors report noticing a decline in the president's energy and articulation during fundraising events.

The White House has pushed back against reports questioning Biden's mental fitness. When faced with inquiries about a January meeting where Biden reportedly spoke softly and paused frequently, allies like Sen. Patty Murray initially defended his engagement. However, Murray has since called for a "much more forceful and energetic candidate" to convince voters of his capability.

Biden's public appearances have become more controlled, with shorter remarks and fewer unscripted interactions. His team has employed strategies like playing music to prevent reporters from asking questions during exits. The president has held fewer news conferences and interviews than any of his predecessors since Ronald Reagan at this point in their terms.

Despite these challenges, Biden has had moments of strong performance, including his State of the Union address and a speech in Blue Bell, Pennsylvania. He's also undertaken high-profile trips, such as visits to Kyiv and Israel.

As the election approaches, the Biden campaign faces the delicate task of addressing age concerns while highlighting the president's accomplishments and vision for the country. But no one really knows whether these strategies can assuage voter worries and maintain party support for Biden's re-election bid.

* The Wall Street Journal contributed to this article.