Sarah Palin is fuelling fresh speculation she could be about to mount a presidential bid.
The former Alaskan governor and 2008 vice presidential candidate rode into Washington on the back of a Harley-Davidson on Sunday, in black jeans, leather jacket and a helmet.
She used a war veteran's motorcycle rally in Washington to launch an East Coast bus tour, designed to energise Americans about the country's founding principles.
The annual Rolling Thunder motorcycle rally honors military veterans.
Ms Palin ignored questions about a presidential campaign and said ''Heck no, I'm an American,'' when asked if she was politicizing the rally.
''I'm out here supporting veterans,'' she told CNN.
In a statement after the rally, she said: ''There's no better way to see DC than on the back of a Harley.''
In addition to the bus tour and a revamped website, Ms Palin has authorized a film about herself that will premiere next month in Iowa.