HARRISBURG, PA (CBS) — Sometime this coming week, look for Governor Wolf to make good on his promise to veto a bill that would impose further restrictions on abortion in Pennsylvania. The issue continues to loom large on the political landscape.

Long before the House gave final approval on Tuesday night, Democratic Governor Tom Wolf had guaranteed a veto of the abortion bill.

So why did majority Republican legislative leaders insist on putting it up for a vote?

Franklin and Marshall College pollster Terry Madonna says genuine beliefs are one factor. But while polls consistently show abortion is not a top-of-the-mind issue for many voters, it is an issue that appeals to the base of each party.

“There aren’t that many middle-of-the-road voters left,” he said. “I mean, these elections are essentially about turnout among your core supporters.”

Even before the House vote Tuesday, Wolf had released an online campaign video about the abortion bill.

While it’s not that moderate voters don’t matter all, Madonna believes the priority for today’s candidates is to fire up the base.