A $1.00 bet on Cruz pays $4.50.
I tend to trust the opinions of those who have money at risk than those who just have an opinion.
Those predictive markets had Scott Walker and even Jeb Bush winning the nomination at one time or the other. It’s just like the stock market. Various stocks go up or down depending on market conditions and latest factors that affect the stock price. It’s no better/worse than any other predictive model.