I should have said Crassus HAD enough wealth, not was said to have. He literally fielded an entire army of over 30,000 and footed the bill himself.

The wealth of Crassus, while impressive, is over-exaggerated; Pompey and Caesar, to identify some contemporaries, had more ready cash on hand as well as overall wealth.

This is not to discourage further discussion, but you may want to check out these posts for an answer. Several of them have the key points credited to /u/xenophontheathenian.

https://www.reddit.com/r/AskHistorians/comments/3jnr52/what_initially_made_caesar_an_attractive_choice/

https://www.reddit.com/r/AskHistorians/comments/3ljy51/what_happened_to_crassus_financial_empire_after/

https://www.reddit.com/r/AskHistorians/comments/2e0wt7/roman_historians_where_did_marcus_licinius/

https://www.reddit.com/r/AskHistorians/comments/2g0jtr/how_rich_was_crassus/