Where does the phrase up the ante come from?

"Up the ante" is a Poker-derived idiom that means to raise the stakes, to put more at risk, both in poker and in one's personal life.

The ante is the enforced bet that poker players must put into the pot before they can play a hand of poker. If you "up the ante," you increase the amount of the bets. Thus, upping the ante means to raise the stakes or increase the risk of a project.

You can "ante up" any amount - some people play for pennies, and some for thousands of dollars.