Washington (CNN) A former Obama senior adviser said it is likely that Democrats will lose their fight to block President Donald Trump's Supreme Court pick, but that doesn't mean the party shouldn't fight.

"I think that it is incumbent upon Democratic leaders and sort of Democratic voices ... to be honest and forthright about expectations here — that we are likely to lose this battle," Dan Pfeiffer told David Axelrod on "The Axe Files," a podcast from the University of Chicago Institute of Politics and CNN.

"But I think we should fight like hell anyway," he said.

The President announced last week he was nominating Brett Kavanaugh to replace retiring Justice Anthony Kennedy. Republicans have a 51-49 seat majority in the chamber and GOP leaders only need 50 votes to confirm Kavanaugh. Senate Majority Leader Mitch McConnell said he expects confirmation hearings to begin "in late August or early September" and predicted Kavanaugh would be confirmed by the beginning of October.

Pfeiffer, who is a CNN contributor, said that although Democrats lack the control in the Senate to stop the confirmation, they must "make people believe in the importance of these court appointments." He noted that he believed that Republicans won the 2016 election in part because they leveraged the power of a potential Supreme Court pick to replace the late Justice Antonin Scalia and said Democrats at the time failed to do the same. Pfeiffer suggested the Democrats ought to be better about messaging ahead of the midterms.

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