I don't vote Democrat because of some weird loyalty to the Democratic Party. I vote Democrat because their public policies are more geared toward helping the average person compared to Republican policies. I also wouldn't vote Republican because of their war on education, women's rights, and the LGBTQ+ community. So to answer the OP, if some miracle occurred and a Republican candidate that had policies that favored workers over CEOs/stockholders, for example, sure, I would cross party lines in a heartbeat. But the Democrats are the best game in town at the moment given my policy priorities.