Supporters of same-sex marriage reached a milestone Tuesday when Maryland and Maine became the first states where voters upheld marriage rights for gay and lesbian couples. While gay marriage has gained the support of courts, legislatures and even President Obama, voters have rejected the question every time it has appeared as a ballot issue.

But Tuesday turned the tide. Washington state voters were poised to uphold gay marriage on Wednesday, with supporters of the referendum declaring victory. Voters in Minnesota turned down an effort to ban gay marriage in the state's constitution. "We can't underestimate the importance of what we saw yesterday," said David Masci, a senior researcher at the Pew Forum on Religion and Public Life. "It's a pretty big deal."

Part of it boils down to demographic changes, he said. Younger voters overwhelmingly backed Obama's election in 2008 and turned out in even larger numbers Tuesday. They're also the group that shows the highest support for gay marriage. Evan Wolfson, president of Freedom to Marry, a New York-based gay rights group, called the results "a powerful demonstration that the center of gravity has dramatically shifted in our direction" after losses at the ballot in 2004 and 2008. "We're working within a huge amount of wind in our sails," he said.

Brian Brown, president of the National Organization for Marriage, which opposes same-sex marriage, downplayed the significance, saying they were the result of heavy political and financial support in four liberal-leaning states.

Heading into the election, gay marriage was legal in six states and the District of Columbia, in each case due to legislation or court orders rather than popular vote. Activists said the results will likely spur pushes for same-sex marriage in states that already have established civil unions for gay couples -- including Illinois, Rhode Island, Hawaii and Delaware. Democratic takeovers of both legislative chambers in Colorado and Minnesota may also prompt moves there to extend legal recognition to same-sex couples.

Those who have argued for decades that legalizing and taxing marijuana would be better than a costly, failed U.S. drug war have their chance to prove it, as Colorado and Washington became the first states to allow pot for recreational use. While the measures earned support from broad swaths of the electorate in both states, they are likely to face resistance from federal drug warriors. As the initial celebration dies down and the process to implement the laws progresses over the next year, other states and countries will be watching to see if the measures can both help reduce money going to drug cartels and raise it for governments.

Both measures call for the drug to be heavily taxed, with the profits headed to state coffers. Colorado would devote the potential tax revenue first to school construction, while Washington sends pot taxes to an array of health programs. Estimates vary widely on how much they would raise. Colorado officials anticipate $5 million to $22 million a year. Washington analysts estimated legal pot could produce nearly $2 billion over five years. Both state estimates came with big caveats: The current illegal marijuana market is hard to gauge; and any revenue would be contingent upon federal authorities allowing commercial pot sales in the first place, something that is very much still in question. Authorities did not say Wednesday whether they would challenge the new laws.

For the first time in history, women will occupy one-fifth of the seats in the Senate, and white men will no longer hold a majority in the Democratic caucus in the House. Those shifts reflect the growing electoral power of women and minority members, and the Democratic Party's determination to harness that energy to build a diverse coalition.

In the Senate, there are 17 women: 12 Democrats and five Republicans. In January, there will be 20: 16 Democrats and four Republicans. Women held all six of their seats up for re-election and Democratic women picked up four: Elizabeth Warren, who is the first woman Massachusetts has elected senator; Mazie Hirono, top right, in Hawaii, the first Asian-American to be elected to the Senate; Tammy Baldwin, right, in Wisconsin, the first openly gay senator; and Heidi Heitkamp in North Dakota. It was a victory for Patty Murray, whose task -- as head the Democratic Senatorial Campaign Committee -- it was to defend her party's majority.

In the House, where Democrats are expected to hold about 200 seats, white men were projected to represent slightly less than 50 percent of the Democratic caucus. It would be the first time that white men did not hold the majority of a major party caucus in the House.

In New Hampshire, voters will send an all-woman delegation to the next Congress. Former Rep. Carol Shea-Porter and Ann McLane Kuster, both Democrats, defeated Republican Reps. Frank Guinta and Charlie Bass. Both of the state's U.S. senators are women. Democrat Maggie Hassan also won the governor's race, making the Granite State the first state with a female governor and all-female congressional delegation.

Nowhere was the fight over ballot measures fiercer than in California, where spending on campaigning for and against 11 measures totaled nearly $370 million, said MapLight. Here are some of the key measures:

Death penalty: Voters also considered an initiative to end the death penalty -- the first ballot-box attempt in three decades. The measure was defeated, with opposition of 52.8 percent, semiofficial state results showed. Law enforcement officials and victims' rights groups said they may push for a ballot measure to streamline the appeals process as soon as 2014.

Three-strikes law: Voters endorsed a measure that would make the three-strikes law somewhat more lenient by imposing a life sentence only for a third felony conviction considered serious or violent.

Genetically modified food labels: Voters rebuffed an effort to make the labeling of genetically modified food mandatory. By 53.1 to 46.9 percent, voters defeated Proposition 37, which would have made California the first state in the nation to require such labels on some produce and processed foods, such as corn, soybeans and beet sugar, whose DNA has been altered. The measure fell victim to a media blitz bankrolled by $46 million in contributions from big biotech companies, including Monsanto Co. Opponents argued that the measure was expensive, bureaucratic and full of illogical loopholes.

Taxes: Voters approved a measure that will raise taxes by $6 billion annually over seven years. Voters heeded the pleas of Gov. Jerry Brown, who said the revenues were necessary to save the state's public schools and balance the budget. The vote -- 54 to 46 percent -- brought an end to an acrimonious, $123 million battle between the governor and conservative opponents.