A radiation-sensitive composition includes a radically polymerizable
component, initiator composition, a radiation absorbing compound, and a
polymeric binder having recurring units that are derived from various
ethylenically unsaturated polymerizable monomers provided that at least
40 mol % of the recurring units have a tertiary carbon atom in the
backbone and the rest of the recurring units have a secondary or
quaternary carbon atom in the backbone. This composition can be used to
provide negative-working imageable elements that can be imaged and
developed to provide lithographic printing plates that have desired
imaging speed and excellent run length without the need for a
post-exposure backing step.