How were the generals of Ancient Rome able to become political leaders?

The political system in Ancient Rome was based on competition with the ruling elite, the military was a key element to the political system of Ancient Rome that was generally based on competition within the ruling class. An individual social standing impacted their political and military roles. War was significant towards Roman expansion to the Northern Hemisphere, it was characterized by; grabbing of land, military might, strategic ability and political capabilities of the generals that determined their political leadership