Washington (CNN) Democratic Sen. Joe Manchin of West Virginia said he believes President Donald Trump would support a bill from him and GOP Sen. Pat Toomey of Pennsylvania to expand background checks on gun sales.

"I really believe he would," Manchin said on CNN's "State of the Union. "In my heart of hearts I believe that."

Manchin said between Trump's varied signals on guns, he thinks there is reason to believe the President would back the legislation and could be the key mover for the bill.

"It's up to President Trump," Manchin said. "That can be a legacy for him."

But he said if a provision from California Democratic Sen. Dianne Feinstein to ban some semiautomatic weapons were included in broader legislation containing his proposal, it would kill his background check measure.

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