The Catholic vote was democrat before Hispanics showed up, and will remain democrat, although most of the diminishing number of whites who remain catholic, are becoming moderate republicans.
The majority of the vote of the members of the Catholic denomination, will continue to vote democrat, it is a democrat voting denomination.
Ronald Reagan (twice) and Bush the Elder both received a majority of the Catholic vote. So did Nixon (once). Over the course of the past three quarters of a century, the trend among Catholics has been away from the Democrats and towards the Republicans. But the overall numbers are close. Except that, as noted previously, church-going Catholics are a strong voting bloc for Republicans.