Rep. Kirsten Gillibrand, D-Hudson, has been tapped by Governor David Paterson to replace Hillary Clinton in the U.S. Senate.
Clinton vacated her seat this week before becoming secretary of state under President Barack Obama.
Mr. Obama telephoned Gillibrand after the announcement and congratulated her.
"Governor Paterson made a wonderful choice in appointing Kirsten Gillibrand to fill Secretary Clinton's seat in the United States Senate," said White House Press Secretary Robert Gibbs. "I am confident she will continue Secretary Clinton's distinguished service to the people of New York."
Paterson's selection has been the focus of rumor and debate for months, ever since Secretary Clinton announced she would vacate the seat she has held since 2001.
Caroline Kennedy, the daughter of former President John F. Kennedy, was considered the front-runner before withdrawing her name from consideration on Thursday.
Paterson and the state's top political leaders gathered at Empire State Plaza in Albany on Friday for the historic announcement.
"Please welcome our next senator and current congresswoman Kirsten Gillibrand," Paterson announced to roaring applause.
"I realize for many New Yorkers, this is the first time you've heard my name and you don't know much about me," Gillibrand said in her acceptance speech. "Over these next two years, you will get to know me. But much more importantly, I will get to know you."
In two years, Gillibrand will have to run for election to fill the remaining two years of Clinton's six year term.
Gillibrand, 42, is a conservative Democrat from Hudson in Columbia County was most recently elected to her second term in the U.S. House of Representatives.
Gillibrand has won kudos from organizations on both the left and right. She has been backed by the National Rifle Association as a supporter of gun rights. And has a perfect score from the American Civil Liberties Union.
A staffer said Gillibrand is pro-gay marriage, a change from past reports that described the congresswoman as anti-gay marriage, but pro-civil unions. Gillibrand is pro-abortion.
Gillibrand is married and a mother of two.