Likely to, announced as, as in Betty bought more of the stock, believing it was due to rise, or The play is due to open next week. [Early 1900s]
Attributable to, because of, as in Due to scanty rainfall, we may face a crop failure. This usage has been criticized by some authorities, but today it is widely considered standard. [Early 1900s] Also see on account of.
Owing or payable to, as in We must give our staff whatever vacation is due to them.