In many of the states that voted on Tuesday, however, including Pennsylvania and Montana, there were only scant signs of protest voting, underscoring the extent of Mr. Trump’s dominance within his party even in a period of extraordinary political adversity. And his advisers point to the relatively high turnout on the Republican side in some states, like New Mexico, as a sign that Mr. Trump’s base is still intensely engaged.
It is not clear how fully Mr. Trump grasps the depths of his political peril; when he was asked on Wednesday about trailing Mr. Biden in the polls, he replied, “I have other polls where I’m winning,” though he did not cite one. At times, his allies have taken unusual steps to try to calm his frustration, including commissioning and then leaking a poll last month that suggested that Mr. Trump had gained ground rapidly on Mr. Biden, people familiar with the efforts said, even as other Republican and nonpartisan polling showed the president’s numbers stagnant.
But Mr. Trump has been lashing out for weeks at some of his political lieutenants, according to people briefed on his reactions, who were not authorized to speak publicly. He blamed them for the difficulty of the campaign, comparing them unfavorably to the operation surrounding Mr. Biden. The president has complained that his fund-raising advantage has diminished, and indeed some of Mr. Trump’s advisers were caught off guard when Mr. Biden raised nearly as much money as the president in April.
“Biden has a team of killers and all I’ve got is a defense,” Mr. Trump has said to allies, taking a decidedly different view of the Biden campaign than most Republicans as well as a good number of Democrats.
Mr. Trump’s campaign has already carried out an organizational shake-up, elevating a trusted adviser, Bill Stepien, to the role of deputy campaign manager and giving him an expansive portfolio. The move came after Mr. Trump spent much of the spring railing bitterly about his campaign manager, Brad Parscale, and other Republicans raised questions about whether Mr. Parscale had sufficient political experience and knowledge to steer a presidential campaign.
Mr. Parscale’s job is safe, several officials insisted, but other changes on the campaign could happen in the coming weeks, according to people close to Mr. Trump.
Across the Republican Party, there is a mood of intense apprehension and hope — though not optimism — that Mr. Trump can stabilize his candidacy and rebuild his political position as he did after several political crises in 2016.