"We're going to get a lot of the Bernie voters by the way, because they didn't treat him right," he told volunteers in Cleveland Friday. "He ran a very, very good campaign and Hillary's people just swamped him."
"I will tell you. I think we're going to get a lot of his voters, because of the trade issues because they understand," Trump added.
The comments are similar to ones Trump gave during his convention speech on Thursday night.
But the Vermont senator responded to Trump's speech by saying his supporters won't back the GOP nominee's "bigotry and divisiveness."
"Those who voted for me will not support Trump who has made bigotry and divisiveness the cornerstone of his campaign. #RNCwithBernie," Sanders tweeted Thursday during the Republican nominee's speech.
"We believe in bringing people together, not dividing them up," he tweeted.
Trump sought to win over some of Sanders' voters who find fault with Clinton and share relatively similar positions with Trump on trade issues.
"Her bad instincts and her bad judgment, something pointed out by Bernie Sanders are what caused the disasters unfolding today," he said in his speech.
Amid some speculation about a significant portion of Sanders supporters who dislike the former secretary of state possibly considering Trump, Sanders took to Twitter to show just how problematic the Republican nominee's policy ideas are for liberals.
"Trump thinks climate change is a 'hoax.' My supporters understand that we must move away from fossil fuels, not expand them. #RNCwithBernie," he tweeted.
Sanders, who endorsed Clinton earlier this month, tweeted out multiple messages outlining policy difference with Trump.
"Still waiting for a single word about covering the 28 million Americans without health insurance. I guess they don't matter much to Trump," he tweeted.
Trump is wrong. The real cause of instability in the Middle East was the Bush-Cheney invasion of Iraq. By the way, where is President Bush," he tweeted.
"What a hypocrite! If Trump wants to 'fix' trade he can start by making his products in the US, not low-wage countries abroad. #RNCwithBernie," he tweeted.