Former Secretary of State Hillary Clinton is expected to formally announce her 2016 presidential candidacy on Sunday.

A source close to Clinton's campaign says that she will make the announcement via online video and Twitter at noon Sunday.

This would be Clinton's second run for the Democratic nomination. She lost to President Barack Obama in 2008.

Sources close to the Clinton team say the strategy this time around will be to "go small." They plan to trade in the big events for more intimate ones in early voting states.

By campaigning heavily in Iowa and New Hampshire, Clinton is hoping to avoid the same stumbles that led to her loss in the 2008 Iowa caucuses.

Her expected return to politics comes two years after she served as President Obama's secretary of state.

Hundreds of Clinton's supporters rallied in lower Manhattan Saturday. The rally, dubbed "Ready for Hillary," was held at the SouthWest NY restaurant. The supporters say they cannot wait for the announcement.

On the Republican side, Sens. Ted Cruz and Rand Paul have both officially declared their runs for the presidential office.