MINNEAPOLIS — The group promoting a constitutional ban on gay marriage in Minnesota is debuting its first two TV ads of a heated campaign today, one that argues it’s important to keep the traditional definition of marriage between opposite sex couples only and another that mentions several ways that definition could be changed through legal or judicial means.

Minnesota for Marriage campaign manager Frank Schubert told The Associated Press the group is spending about $175,000 to air the two ads throughout October. With their chief rival campaign already on TV the last two weeks, the ads signal the five-week homestretch for the multimillion-dollar political battle over gay marriage in Minnesota.

Both ads avoid an aggressive tone, with one featuring a narrator who says that “everyone has a right to love who they choose.” But together they argue that male-female marriage has been a building block of society for centuries, and that inserting that definition into Minnesota’s constitution would prevent judges or elected officials from changing it without the OK of voters.

“Marriage is more than a commitment between two loving people,” an unseen narrator says in one ad, over images of straight couples getting married, raising children and showing affection. “It was made by God, for the creation and care of the next generation.”

Minnesotans United for All Families, the group trying to defeat the amendment, has run two TV commercials so far. One features a heterosexual Minnesota couple talking about how they oppose the amendment thanks to the influence of a gay couple in their neighborhood that they got to know. Another features a man who calls his own marriage the most important thing in his life, and says the state’s constitution shouldn’t deny that to anyone.

Describing the content of the new ads, Minnesotans United campaign manager Richard Carlbom declined to issue specific criticisms and instead argued against the amendment’s passage. Carlbom said putting a gay marriage ban in the constitution “would limit the freedom to marry for some Minnesotans just because of who they are.”

“It permanently singles out and excludes gay and lesbian couples from the love, commitment and responsibility that marriage brings,” he said. He added that “no one wants to be told it’s illegal to marry the person you love.”

The two new ads are the first on TV from gay marriage opponents in any of the four states with the issue on the ballot this fall — Minnesota, Maine, Maryland and Washington. Schubert, the country’s leading political strategist for campaigns against gay marriage, is leading his side’s effort in all four states.

In previous TV ads he produced in California in 2008 and other states, Schubert raised concerns that state-sanctioned gay marriage could expose children to influences and beliefs not approved by their parents. Neither of the Minnesota ads resurrect those claims, which often outraged gay activists and their allies.

Schubert said the Minnesota campaign hopes to air more ads. He wouldn’t say what future ads might include but that “we’re certainly going to be talking about what would happen if marriage were to be redefined.”

That could depend on the group’s fundraising in the five weeks to Election Day. The $175,000 ad buy is more than a third of Minnesota for Marriage’s $484,000 still in the bank as of Sept. 18, according to a state financial disclosure report. Leaders of Minnesota’s Catholic diocese, allied with Minnesota for Marriage, last week sent a letter to 400,000 Catholic households asking for donations to Minnesota for Marriage so it could broadcast more commercials.

The group continues to raise funds aggressively, Schubert said. They “poured everything we have into these initial ads and are working hard to raise the funds we need to finish the campaign,” he said.

Minnesotans United has maintained a financial advantage, raising millions more overall and keeping $266,000 more in the bank as of Sept. 18 after making a $1 million down payment on TV airtime earlier in the year.

If passed, the gay marriage amendment would toughen the state’s existing statutory ban on gay marriage by putting it in the constitution. A Star Tribune poll of 800 likely voters taken in mid-September found a dead heat with the poll’s margin of error, with 49 percent in support, 47 percent against and 4 percent undecided.