It's not just same-sex couples in Maine, Maryland and Washington who are celebrating the recent legalization of gay marriage -- the state treasury also has something to sing about. New research suggests that marriage equality will boost the states' economies in a big way.

The Williams Institute at UCLA Law reported Monday that wedding spending by same-sex couples in the three newest states to approve gay marriage may generate more than $166 million over the next three years.

The Institute estimates that same-sex couples in Maine will collectively spend $15.5 million, Maryland couples will spend $62.6 million and Washingtonians will spend $88.5 million on weddings. The estimates are based on 2010 U.S. Census data and each state's average wedding spending. The researchers assumed that half of the states' same-sex couples (that's nearly 18,000 of about 35,000 gay couples in all three states combined) will marry within three years.

Though same-sex marriage is already legal in Connecticut, Iowa, Washington, D.C., Vermont, New Hampshire, New York and Massachusetts, on Nov. 6 voters in Maine, Maryland and Washington were the first in the country to approve same-sex marriage by popular vote (in the other states, marriage equality was legalized by state legislation). Minnesota voters also rejected a ban on same-sex marriage.

Economists have followed gay marriage's impact on the wedding industry and local economies since Massachusetts became the first state to legalize same-sex unions in 2004. The Williams Institute found that from May 2004 to September 2008, the Massachusetts economy enjoyed a $111 million boost as a result of gay marriage legalization.

And in July, CNN Money reported that the legalization of gay marriage in New York boosted New York City's economy by $259 million in just one year.

“The same number of people have been getting married every year for the last 20 years,” Carley Roney, co-founder and editor in chief of TheKnot.com, told The Daily Beast. “Gay marriage is literally the only thing that has the potential to change the size of the wedding industry.”

For gay-friendly wedding vendors and venues in Maryland and Maine, check out the slideshow below.

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  • Portland, ME: <a href="http://www.minotts.com/">Minott's Flowers</a> has the stamp of approval from <a href="http://www.gayweddings.com/wwvendor?vid=4a1b4a7eecc0cab2">GayWeddings.com</a>.

  • Freeport, ME: <a href="http://emilycarterflowers.com/">Emily Carter Floral Designs</a> is a popular vendor on <a href="http://gayweddings.com/wwvendor?vid=b57198b0677b7dc9">GayWeddings.com</a>.

  • Auburn, ME: <a href="http://www.ahimsacustomcakes.com/">Ahimsa Custom Cakes</a> sculpts all kinds of tasty treats and is vetted by <a href="http://www.soyoureengayged.com/vendor-list/food/ahimsa-custom-cakes-llc/">So You're EnGAYged</a>.

  • Falmouth, ME: <a href="http://www.europeanbakeryinc.com/wedding-cakes.php">European Bakery Inc.</a> has been baking wedding cakes for over 20 years and is approved on <a href="http://www.gayweddings.com/wwvendor?vid=5fd7e4b8a0fa1717">GayWeddings.com</a>.

  • Eliot, ME: <a href="http://www.blackbunnybakery.com/">Black Bunny Bakery</a> is family-owned and confirmed gay-friendly by <a href="http://www.gayweddings.com/wwvendor?vid=f18c92a3937ff092">GayWeddings.com</a>.

  • Rockport, ME: Get married on the ocean at <a href="http://www.samosetresort.com/">the Samoset Resort</a>. The gay-friendly venue checks out with <a href="http://www.gayweddings.com/wwvendor?vid=1a9c6efbf2e92ed8">GayWeddings.com</a>.

  • Boston, MA: Host hotel for Boston Pride 2012, <a href="http://www.reverehotel.com/#meet/celebrations">Revere Hotel</a> has multiple spaces for elegant same-sex weddings according to <a href="http://www.gayweddings.com/">GayWeddings.com</a>.

  • Boston, MA: Gay-owned <a href="http://www.taylorhouse.com/">Taylor House</a> is already a popular venue for same-sex weddings. Vetted by <a href="http://www.purpleunions.com/el/t/taylor-house-boston.html">Purple Unions</a>.

  • New York Area: <a href="http://www.jandjphotography.net/same-sex-weddings">J & J Photography</a> offers steep discounts for gay couples. Found via <a href="http://www.engaygedweddings.com/ny/photographers/j-and-j-photography.html">So You're EnGAYged </a>.

  • New England Area: <a href="http://avennastudios.com/blogroll/mass-moca-museum-of-contemporary-arts/">Avenna Studios</a> already has experience beautifully photographing same-sex weddings and is approved by <a href="http://www.gayweddings.com/wwvendor?vid=8da055a3a5719f75">GayWeddings.com</a>.

  • Boston, MA/NYC: Lesbian-owned<a href="http://www.14stories.com/"> 14 stories</a> was the first wedding planning company to specialize in same-sex marriages.

  • Washington, D.C.: <a href="http://www.greenworksflorist.com/">Greenworks Florist</a> designed floral arrangements for Vera Wang's 2008 Bridal Show and was deemed gay-friendly by <a href="http://www.gayweddings.com/wwvendor?vid=fb5acf185f94b3ae">GayWeddings.com</a>.

  • Baltimore, MD: <a href="http://www.myflowerboxevents.com/">My Flower Box Events</a> is an incredibly popular florist on <a href="http://www.gayweddings.com/wwvendor?vid=002d73f5b24afaea">GayWeddings.com</a>.

  • Baltimore, MD: <a href="http://www.baltimorecakery.com/">Baltimore Cakery</a> is a recent addition to town, but already has positive reviews on <a href="http://www.gayweddings.com/wwvendor?vid=a5e97141181a8262&x-tab=rev&p=1">GayWeddings.com</a>.

  • Baltimore, MD: The ever-popular <a href="http://www.charmcitycakes.com/">Charm City Cakes</a> has plenty of experience creating cakes for same-sex weddings and is a <a href="http://www.bizjournals.com/washington/news/2012/11/07/maryland-same-sex-marriage-expected-to.html">supporter of marriage equality</a>.

  • Baltimore, MD: <a href="http://www.chasecourt.com/2Commitment-Ceremonies.html">Chase Court</a> has a long history of welcoming gay couples in the community. They're also vetted by <a href="http://www.gayweddings.com/wwvendor?vid=5bc2056a6716c05e">GayWeddings.com</a>.

  • Multiple Locations: <a href="http://www.marriott.com/marriott/marriott-gay-travel/gay-wedding-venues.mi">The Marriott Hotel chain</a> has a whole section of their site dedicated to same-sex weddings.

  • Baltimore, MD: Visit Baltimore, the city's tourism bureau, has already launched <a href="http://www.baltimore.org/lgbt-weddings/">this handy site</a> for same-sex couples ready to plan their Big Day.

  • Columbia, MD: Ginny Carson officiates all marriage ceremonies through <a href="http://www.ceremoniesncelebrations.com/">Ceremonies and Celebrations</a> and has rave reviews on <a href="http://gayweddings.com/wwvendor?vid=1387a85c691341e8">GayWeddings.com</a>.

  • Mid-Atlantic: <a href="http://www.eikonphoto.com/">Eikon Photography</a> has lovely examples of same-sex wedding photos on their site, plus they're featured on <a href="http://www.purpleunions.com/el/e/eikon-photography.html">Purple Unions</a>.

  • Massachusetts/Online: <a href="http://www.outvite.com/">Outvite</a> features LGBT custom printed stationary for all occasions, including same-sex weddings.

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