BRASILIA, Brazil — The cost of building the soccer stadium in Brazil's capital for next month's World Cup has nearly tripled to $900 million in public funds, and government auditors allege that's largely due to fraudulent billing.

It's now the world's second-most expensive soccer arena, and Brasilia doesn't even have a major professional team. Critics call it the poster child for out-of-control spending and mismanagement, or worse.

An Associated Press analysis of data from Brazil's top electoral court shows skyrocketing campaign contributions by companies involved in the most World Cup projects — findings that will add to deep suspicions among Brazilians that preparations for soccer's premier event have been tainted by corruption.

Anger over perceived corruption already helped fuel huge protests last year, and there are fears more unrest could mar the Cup.