After laying waste to the GOP's fiscal agenda by vetoing the entire budget, DFL Gov. Mark Dayton followed up by punching a hole in their social agenda.

On Wednesday, Dayton vetoed restrictions on abortion and symbolically vetoed a move to put a constitutional ban on same-sex marriage on the 2012 ballot.

"I urge Minnesotans to reject this mean-spirited, divisive, un-Minnesotan and un-American amendment," Dayton wrote in issuing his figurative marriage veto. "Minnesotans are better than this."

But the Republican majority that controls the Legislature says they are reflecting what mainstream Minnesotans want -- a constitutional definition of marriage as the union of a man and woman.

He's "trying to make a political statement," said Tom Prichard, president of the Minnesota Family Council, a key backer of the marriage amendment. "The governor has one vote. ... The audience that matters is the people of Minnesota, not what the governor is going to say."

Dayton has no power to block the amendment question from appearing on the 2012 ballot. Governors cannot stop constitutional amendments that win legislative approval.

Sending a message

But the proposed amendment, approved by a majority of lawmakers after emotional debate, arrived on his desk as a bill. So he took the opportunity to deliver a powerful message.

"Symbolic as it may be, I am exercising my legal responsibility to either sign or veto it," he said.

For amendment opponents, bruised by the legislative vote, the action had power.

"It is far, far more than symbolic," said Sen. Scott Dibble, DFL-Minneapolis, who is gay. "It improves the sense of optimism and hope that seemed to be eluding us this session. ... We've certainly taken punch to the gut, but we're still standing."

Dayton predicted the amendment will fail when it comes before voters next year.

The governor also doused the hopes of activists against abortion. Wednesday, as expected, he vetoed two measures that had been their key lobbying efforts this year.

One of those measures would have prohibited abortion after 20 weeks. The other would have banned the state from paying for abortions for low-income women.

Dayton called the 20-week ban "unconscionable." As for the other abortion bill, Dayton said "all women deserve to be healthy and safe. I will not approve a bill that infringes upon a woman's constitutionally protected rights, discriminates against a woman because of her socio-economic status and does not protect her health and safety."

Scott Fischbach, executive director of Minnesota Citizens Concerned for Life, said the vetoes were unfortunate. The bills, he said, "are common-sense mainstream pieces of legislation."

Backers said they could go around the governor with constitutional amendments, but that was not their preference.

That route, Fischbach said, is "always a possibility, but we want to work within the system."

Dayton may face the abortion language again. Fischbach said he would hope that if there is a special session, the measures would be revived.

More vetoes coming?

The governor is also due to act soon on the Legislature's voter ID measure, another key Republican priority. The measure would require voters to present photo identification before casting ballots and make other significant changes to election law.

Dayton said Wednesday that he had met with two lawmakers and the secretary of state to discuss the measure. Sen. Katie Sieben, Rep. Paul Thissen and Secretary of State Mark Ritchie all oppose the bill. Dayton said their advice may be "persuasive."

Minnesotans have already been persuaded. A recent Star Tribune poll found that 80 percent support the proposal.

Lawmakers introduced a constitutional amendment requiring the extra show of voter validity but did not bring the amendment to the House or Senate floors.

Rachel E. Stassen-Berger • Twitter: @rachelsb

VETO LETTERS

• On abortion: www. startribune.com/a431

• On gay marriage: www. startribune.com/a432