Now many Democrats say they’re watching nervously as polls start to trend in Republicans’ favor — and worry they’re witnessing the beginning of a slow-motion train wreck that they have no idea how to stop.

There are still widespread disagreements within the diverse 193-member caucus about what campaign message Democrats should rally around in the final months before the midterms and even who should be the party’s chief messenger.

Some Democrats worry a rerun of the Republican playbook employed in the past several cycles — painting House Minority Leader Nancy Pelosi (D-Calif.) as the GOP’s central villain — will again be successful in denying them the House majority.