Washington: The 113th US Congress will have at least 19 women senators, the highest ever in the country's history.
Joining the Senate will be Republican Deb Fischer (Nebraska) and Democrats Tammy Baldwin (Wisconsin), Mazie Hirono (Hawaii) and Elizabeth Warren (Massachusetts).
All six Democratic women up for re-election - Senators Maria Cantwell (Washington), Dianne Feinstein (California), Kirsten Gillibrand (New York), Amy Klobuchar (Minnesota), Claire McCaskill (Missouri) and Debbie Stabenow (Michigan) - won their races, the Huffington Post reported.
There are currently 17 female US senators, which had also been a record number. Senators Kay Bailey Hutchison (Republic of Texas) and Olympia Snowe (Republic of Maine) are both retiring, meaning the next Congress will have just four female Republican senators.
Republican Shelley Berkley (District of Nevada) lost her Senate race to incumbent Dean Heller, while Democrat Heidi Heitkamp's race in North Dakota was too close to call.
Five Republican female candidates including Wendy Long, Elizabeth Emken and Linda Lingle lost Wednesday.
Linda McMahon in Connecticut and Heather Wilson in New Mexico also lost.
Female candidates were a key part of the Democratic Party's strategy to keep the Senate, with candidates like McCaskill, Baldwin and Warren in some of the most competitive races in the country.
The Democratic Senatorial Campaign Committee, led by Senator Patty Murray (District Washington), consistently touted the fact that it had recruited a record number of female candidates.
"When we started this campaign, no one, and I mean no one gave us a chance. But we went out and built the best Senate campaigns in the history of the country," Murray said.
"We recruited some of the highest quality candidates, including a record number of women. Democrats never let up and now we will retain our majority in the United States Senate," Murray added.
"Democratic women in the Senate were the first line of defense against the Republican war on women," added EMILY's List President Stephanie Schriock.
"Voters saw the role they played, and they trust them to lead on the issues that matter to women and families. That's why they sent every single Democratic woman up for re-election to the Senate back to Washington. It's an incredible testament to the good work these women do in Washington," Schriock said.
Issues that disproportionately affect women - from reproductive rights to Medicare to jobs - were front and centre of the 2012 campaign.