WASHINGTON (AP) — Threatening to tank Congress' massive COVID relief and government funding package, President Donald Trump's demand for bigger aid checks for Americans is forcing Republicans traditionally wary of such spending into an uncomfortable test of allegiance.

On Thursday, House Democrats who also favor $2,000 checks will all but dare Republicans to break with Trump, calling up his proposal for a Christmas Eve vote. The president's last-minute objection could derail critical legislation amid a raging pandemic and deep economic uncertainty. His attacks risk a federal government shutdow...