Q&A: Single-issue (pro-life) voting is legitimate because abortion is a deal-breaker moral issue. Mike would vote for a pro-life candidate with bad economic policies because saving lives outweighs financial pain.

Abortion is a deal-breaker issue for Mike. Even if a pro-life candidate would bankrupt the country, the moral weight of saving lives exceeds the cost of financial hardship. It doesn't have to be the only issue, but it's a non-negotiable prerequisite.