WASHINGTON — Undecided Catholic votes are a swing voting block, but fairly show up to the polls, a new report found. The report, conducted by Untold Research on better of Network, a Catholic social justice lobby, found “Catholics are swing votes in the true sense of the term.” It found that just 4% of respondents who described them as Catholics and as undecided, uncommitted votes in this election cycle did not vote at all in the past three presi…