Happy birthday to my friend and constituent Hillary Clinton! twitpic.com/b7m15z— Nita Lowey (@NitaLowey) October 26, 2012
Happy birthday to my mentor, role model and friend, Hillary Clinton!— Kirsten Gillibrand (@SenGillibrand) October 26, 2012
Sen. Mark Udall (D-Colo.) and Rep. Emanuel Cleaver (D-Mo.) also sent birthday tweets.
The former first lady turned 65 on Friday. She does not have a public Twitter account.
The official State Department schedule has the whole day blocked off for Clinton to celebrate her birthday, and includes a note that it "doesn't get more closed press than this," meaning the media is not invited to cover any plans. Clinton will be back on a plane Monday for a three-day trip to Algeria, Bosnia and Herzegovina, Serbia, Kosovo, Albania and Croatia.
Updated at 6:09 p.m.