Story highlights Democrats are wary of triggering a fight that could end the Senate filibuster

Trump is set to make his announcement Tuesday night

Washington (CNN) Senate Democrats are weighing whether to avoid an all-out war to block President Donald Trump's upcoming Supreme Court pick, instead considering delaying that battle for a future nomination that could shift the ideological balance of the court, sources say.

Democrats privately discussed their tactics during a closed-door retreat in West Virginia last week. And a number of Democrats are trying to persuade liberal firebrands to essentially let Republicans confirm Trump's pick after a vigorous confirmation process -- since Trump is likely to name a conservative to replace the late conservative Justice Antonin Scalia.

The reason for the tactic: Republicans are considering gutting the filibuster for Supreme Court nominees if Democrats stay largely united and block Trump's first pick. By employing the so-called "nuclear option," Senate Majority Leader Mitch McConnell could move to reduce the threshold for clearing a filibuster from 60 votes to 51 votes.

That would mean Democrats could lose leverage in the next Supreme Court fight if Trump were to replace a more liberal justice, since the GOP now has 52 seats in the Senate.

Preserving the filibuster now could give Democrats more leverage in the future, proponents of this strategy say. But it would enrage the Democratic base that wants a furious Democratic response to Trump's court pick.

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