House Speaker Paul Ryan will not run for re-election in November, according to a report Wednesday from Axios — a move that will significantly bolster Democrats’ ambitions of retaking the chamber in the November midterms.

For the 48-year-old Republican, long rumored to be leaving office, the decision to stand down was taken in consultation with confidants Tuesday night, Axios reports.

The decision has been confirmed by multiple other journalists; Ryan is expected to inform his staff as soon as Wednesday morning.

One Republican described the shockwaves this would send through Washington:

“This is a titanic, tectonic shift. This is going to make every Republican donor believe the House can’t be held.”

A spokesperson for Ryan was not immediately available to comment on the report.