Polls suggest that somewhere between a third and half of Democratic voters see themselves as moderates, though the label is vague enough to cast doubt on the group’s cohesion.
That bloc, these candidates and their advisers acknowledge, could lose influence if a herd of self-styled pragmatists end up stampeding into the Democratic contest, atomizing the center even as progressive competitors carve up the left. It is also highly uncertain that Democrats, who celebrated the election of many women and candidates of color in 2018, would turn quickly in 2020 to nominating a white man with narrower governing ambitions.
In the early primary states, much of the action so far has focused on proudly liberal, potentially history-making candidates, including Ms. Warren and Senators Kamala Harris of California and Kirsten Gillibrand of New York.
But former Gov. John Lynch of New Hampshire, a centrist Democrat, said he saw a clear opening for a candidacy pitched at the middle, one that is attentive to matters like climate change but also sensitive to deficits and debt. Mr. Lynch named Mr. Biden and Mr. Bloomberg as the two most compelling possibilities.
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