Former President Donald Trump and his allies are seizing on routine election processes as signs of fraud in the critical battleground state of Pennsylvania, amplifying allegations, videos and litigation around purported voting irregularities even as local election officials push back.

The playbook is familiar: Like in 2020, Trump’s campaign is spreading viral videos of supposed wrongdoing and promising its eager supporters a legal showdown, which experts fear could be used to contest the results of the election if he loses.