Answer:
The members of the House of Commons.
Step-by-step explanation:
The line "I have nothing to offer but blood, toil, tears and sweat." was said by Churchill on May 13, 1940 when he requested for a vote of confidence in the House of the Commons regarding his new formed party.
Churchill's speech is believed to have been so powerful that it greatly inspired both the Labour and Conservatives for the first time. Thus, Churchill's audience were the members of the House of Commons.