Trump, the Republican nominee, released an open letter early Tuesday from 88 retired generals and admirals citing an urgent need for a "course correction" on America's national security policy.
"We believe that such a change can only be made by someone who has not been deeply involved with, and substantially responsible for, the hollowing out of our military and the burgeoning threats facing our country around the world," the military leaders wrote. "For this reason, we support Donald Trump's candidacy to be our next commander-in-chief."
According to Trump's campaign, the letter was organized by Rear Admiral Charles Williams and Major General Sidney Shachnow, a Lithuanian-born Holocaust survivor.
Clinton's campaign is spending big to undercut Trump's message in a new TV ad also released Tuesday, titled "Sacrifice."
Specifically, the ad shows military veterans watching some of the New York billionaire's more provocative statements, including his claim to know more about the Islamic State group than military generals and his criticism of Arizona Sen. John McCain, a former prisoner of war. It also features Trump's claim that he sacrificed a lot compared to families who have lost loved ones in conflict.
"Our veterans deserve better," reads a line at the end of the ad, which is airing in Ohio, Florida, Iowa, Nevada and Pennsylvania.
The conflicting messages come as the candidates prepare to court voters in Southern states with significant veteran populations. The pair is also set to appear at an MSNBC forum on Wednesday night on national security.
Trump is scheduled to campaign in Virginia and North Carolina on Tuesday, two critical states in his path to the presidency. Trump's afternoon event in Virginia Beach will focus on national security, and he's expected to meet with parents of soldiers later in the day.
Clinton and her running mate, Tim Kaine, were making a pronounced pitch on national security and defense policy on Tuesday, fanning out to military-rich communities of Tampa, Florida, and Wilmington, North Carolina. At every stop, Clinton argues that Trump is temperamentally unfit to serve as commander-in-chief, warning that his bluster would damage the nation's longstanding alliances.
A Clinton victory in Florida would make it virtually impossible for Trump to overcome her advantage in the race for 270 electoral votes.
Clinton has gotten help from the Republicans in questioning Trump's capacity to serve as commander in chief. Dozens of GOP national security leaders released a letter last month warning that Trump would risk the nation's "national security and well-being."
Want to enjoy 'Zen' reading - with no ads and just the article? Subscribe todaySubscribe now