Republicans working to dump Donald Trump believe their efforts got a big boost from the firing of Trump’s campaign manager on Monday, but their lack of organization could prove to be too little and too late.

Hours after the Trump campaign dismissed Corey Lewandowski as campaign manager, Courageous Conservatives PAC which supported Ted Cruz in the Republican primary — distributed a fundraising email seeking money, “to pressure Rules Committee members to do the right thing” and unbind delegates at the GOP convention.