Former speaker is latest target of mailings sent to various Congress members in the lead-up to the midterm elections

California representative Nancy Pelosi’s office received “a suspicious letter” on Wednesday in what appears to be the latest incident of ill-intentioned mailings targeted at US Congress members before the midterm elections.

The offices of more than three dozen members of Congress across the political spectrum have received envelopes containing white powder in recent days. One lawmaker’s office said preliminary tests indicated the powder was not hazardous.

Incumbent Mike Lawler is fending off a challenge from Democrat Cait Conley in state’s 17th congressional district

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Elon Musk’s Super Pac has spent more than $500,000 in New York’s highly competitive 17th congressional district race to help Mike Lawler, the Republican incumbent, hold on to his seat.

Lawler, a moderate Republican, is fending off a challenge from Democrat Cait Conley in the Hudson valley. It is among the most-watched races that could determine whether Republicans hold on to their majority in Congress.