Final answer:
Crassus gained popularity through his participation in suppressing Spartacus' revolt, forming the First Triumvirate with Julius Caesar and Pompey, and using his wealth to increase his influence, although his quest for military glory led to his downfall.
Step-by-step explanation:
To gain more popularity, Crassus leveraged his wealth and political alliances. He achieved renown in Rome by successfully suppressing the slave rebellion led by Spartacus and by aligning with other powerful figures such as Julius Caesar and Pompey to form the First Triumvirate. Crassus utilized his substantial resources to support disaffected wealthy Romans, which added to his fortune and influence. Despite all this, his ambition also led him to seek military glory, notably in an ill-fated campaign against the Parthian Empire which ended in his defeat and death.