ST. PAUL, Minn. (AP) – A national group opposed to gay marriage says it will spend $500,000 to defeat Republican lawmakers in Minnesota who vote to legalize gay marriage.

The National Organization for Marriage issued the warning Monday. The group previously contributed more than $2 million to last fall’s failed campaign to ban gay marriage in Minnesota constitution.

Bills to legalize gay marriage are likely to be introduced at Minnesota’s Capitol this week.

One Republican senator, Branden Petersen, already says he’ll support it. But the National Organization of Marriage says that’s a “career-ending” vote for Republicans. The group has helped fund conservative primary challengers to Republicans in other states who voted in favor gay marriage.

NOM says it will also financially support Democrats who vote against legalizing gay marriage.

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