Story highlights Rod Rosenstein currently serves as the US Attorney in Baltimore

If confirmed, Rosenstein would oversee any potential investigation of the Trump campaign's alleged ties to Russia

Washington (CNN) Democrats aren't finished with Attorney General Jeff Sessions, and they're using the Senate confirmation hearing for his potential second in command as an opportunity to grill him on the Trump campaign's potential ties to Russia and the President's baseless claim of being wiretapped by his predecessor.

Democrats on the Senate Judiciary Committee pressed Rod J. Rosenstein, President Donald Trump's nominee for deputy attorney general, almost exclusively on the Russia investigation and whether Sessions told the truth in his own confirmation hearing when he said he had not met with any Russian officials.

In one very terse exchange, Sen. Al Franken, a Minnesota Democrat, said he was doing everything he could to not accuse Sessions of lying in his testimony before the committee. Franken had asked Sessions during his confirmation hearings how he would handle any potential contacts between the Trump campaign and Russian officials and Sessions responded, "I did not have communications with the Russians."

Sessions did not say that he met twice with the Russian ambassador to the US, Sergey Kislyak, which angered Democrats last week. But Sessions poured fuel on the fire Monday afternoon when he submitted a follow-up letter arguing that he had answered Franken's question truthfully.

"I think Sen. Sessions should come back. I think he owes it to this committee to come back. And he should explain himself," Franken said Tuesday. At the end of his comments, in which Franken dubbed Sessions' response "insulting," Senate Judiciary Committee Chairman Chuck Grassley accused Franken of stepping over the line.

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