(CNN) - Sen. Kay Hagan of North Carolina on Wednesday became the latest Democratic senator to unveil support for same-sex marriage, saying on Facebook the "time has come."
"After much thought and prayer, I have come to my own personal conclusion that we shouldn't tell people who they can love or who they can marry," she wrote.
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She joined a chorus of Democratic senators this week who rolled out support for same-sex marriage. The endorsements came as the Supreme Court heard oral arguments on two cases-the ban against same-sex marriage in California and the 1996 Defense of Marriage Act, which excludes same-sex married couples from certain federal benefits.
Sen. Jon Tester of Montana and Sen. Mark Warner of Virginia also backed same-sex marriage on Facebook this week, following Sen. Claire McCaskill of Missouri, who announced support on her Tumblr page Sunday night.
In addition, Sen. Mark Begich of Alaska endorsed the issue on Facebook, though the Human Rights Campaign, a group that advocates gay rights, notes that he was already considered a supporter.
Meanwhile, Sens. Jay Rockefeller of West Virginia and Tim Johnson of South Dakota said this week they no longer support DOMA.
The sea change was also referenced in Wednesday's hearing at the Supreme Court.
"As far as I can tell, political figures are falling all over themselves to endorse your side of the case," Chief Justice John Roberts, a conservative, said to the lead attorney challenging DOMA, as he was trying to get a grasp on where the shift was coming from.
So, are these Democratic senators simply jumping on the proverbial bandwagon, or are they using the timing of the Supreme Court cases to roll out their support? Or, perhaps the slew of new poll numbers showing stronger support for same-sex marriage may be having an impact, and the senators don't want to seem behind the curve.
Jonathan Rauch, a guest scholar at the Brookings Institution in Washington, said it can be all of the above.
"There's also conviction," he said. "Quite a number of these people have quietly supported same-sex marriage for a while and were waiting for a political moment when the issue had momentum."
How much of politics is at play, though? McCaskill and Tester are from states with large swaths of conservative voters, but they don't face re-election until 2018, giving them plenty of time to fall in line with their party but not face immediate consequences at the polls from those in their base who disagree.
At the same time, Hagan, Begich, and Warner all come from more moderate-to-conservative states as well, yet they're up for re-election next year. However, Rauch suggested, that doesn't mean their political survival is at stake.
"They're politicians, so politicians always think about politics. But in this case politics and conviction are pointing in the same direction," said Rauch, who also authored the book, "Gay Marriage: Why It Is Good for Gays, Good for Straights, and Good for America."
On the GOP side, Sen. Rob Portman of Ohio is the only sitting Republican senator who has voiced support, an announcement he made earlier this month, citing his gay son as a big reason for his change of heart.
Eight Democrats in the Senate, meanwhile, have yet to voice support for same-sex in general, an issue that their party endorsed in its platform last year.
According to the Human Rights Campaign Congressional Scorecard, those include: Mark Pryor of Arkansas, Bob Casey of Pennsylvania, Bill Nelson of Florida, Tom Carper of Maryland, Joe Manchin of West Virginia, Mary Landrieu of Louisiana, Heidi Heitkamp of North Dakota, and Joe Donnelly of Indiana. (Johnson of South Dakota was also listed as a senator who hasn't supported same-sex marriage, but given his reversal on DOMA this week, that could change.)
While Rauch said the public is sure to see more "conversations" in the future, he doubts some of these senators are going to "risk re-election over this issue if they don't have to."