House Republicans are now gathering in their Capitol basement conference room for a previously unscheduled meeting called by House Speaker John Boehner (R-Ohio).

Such meetings are usually held Tuesday mornings, but tonight's gathering comes as Boehner and his leadership team are attempting to ensure passage of "Plan B," the speaker's proposal to raise tax rates on Americans earning more than $1 million annually.

The meeting may indicate that Boehner doesn't have enough votes in the House to pass the plan tonight. 

Members are walking into the room in small groups; few appear happy. But loud cheers were heard as the meeting began around 7:50 p.m. ET.