Side bets at casino table games exist for a couple of reasons. For players, they open the possibility of larger jackpots than standard bets at their games of choice. For casinos, side bets enhance revenues with house edges that are higher than on standard games.

Those larger payoffs aren’t necessarily lifestyle-changing. The 21 + 3 bet at blackjack pays 9-1 — larger than the even-money on standard bets, but not exactly slot-like riches.

But some do induce lottery-style dreams. The Millionaire Maker version of the six-card bonus bet at Three Card Poker is one of those.

An Atlantic City reader wrote to say he’d spotted Millionaire Maker with its $1 million top prize and wanted to know the odds before he took the plunge. “I’m all for winning a million dollars,” he wrote, “but how much of a chance do I really have?”

All versions of the six-card bonus bet combine the player’s three cards and the dealer’s three. Initial versions paid only on the best five-card hands that could be made from those six.

Later, a pay table was introduced that paid a bigger jackpot on a six-card royal, with the rest of the payoffs coming on five-card hands. Millionaire Maker takes that a step further, with big bonanzas on six-card royals — 9 through Ace of the same suit — as well as five card hands ranging down to three of a kind.

With a $5 minimum bet required, the Millionaire Maker pay table looks like this: Six-card royal in diamonds, $1 million; six-card royal in other suits, $100,000; five-card royal, 1,000-1; five-card straight flush, 200-1; four of a kind, 50-1; full house, 20-1; five-card flush, 15-1; five-card straight, 10-1; three of a kind, 5-1.

Note that the top two payoffs are expressed in dollars while the remainder are in odds-to-1 — the way the website for Atlantic City’s Borgata Hotel, Casino and Spa lists the pay table. That’s to tell you the top jackpots do not increase if you bet more. If you bet the minimum $5, the six-card royal pays $1 million. If you bet $10, $100 or more, the payoff is still $1 million.

Only the royal and straight flush are capped. On the five-card hands, payoffs are proportional to your bet, so that a full house brings $100 on a $5 bet or $200 if you bet $10.

A consequence is that the house edge is at its lowest when you bet the minimum. Michael Shackleford at calculated the house edge at 18.1 percent for a $5 bet. But for portions of the wager that exceed $5, the house edge rises to 19.38 percent.

To me, an 18.1 percent house edge is a clear signal to focus on the main game rather than the side bet. The house edge on the ante-play bet at Three Card Poker is 3.37 percent of your ante or 2.01 percent of total action. On the Pair Plus portion of the game, the house edge is 7.28 percent on the most common pay table, while the Borgata, which appends a 100-1 pay on mini-royals to the common pay table, has a 6.82 percent house edge.

I generally stick to ante-play and skip Pair Plus, but you can see that both options on the main game have a lower house edge than Millionaire Maker.

Finally, let’s get back to the reader’s original question of how much chance he has of winning $1 million.

There are 20,358,520 possible six-card hands. Only one of those is a royal in diamonds. A player who wins that prize is very, very, very lucky indeed.

Look for John Grochowski on Facebook and Twitter (@GrochowskiJ).