sentences:  Chase emerged as the most prominent potential intra-party challenger, and Senator Samuel C. Pomeroy led a covert campaign for Chase's nomination.Much of the support for Chase came from abolitionists who were frustrated by Lincoln's unwillingness to push for the immediate end of slavery and his willingness to work with conservative Unionist leaders in the South.Pomeroy's attempts to galvanize support for Chase backfired as they generated a groundswell of support for Lincoln's re-nomination, and Chase announced in early 1864 that he was not a candidate for the presidential nomination.