Hundreds of thousands of people have taken to the streets in Mexico to support the left-wing candidate in the disputed 2 July presidential elections.
"Hold on, the people are rising," they chanted as they marched to Zocalo, Mexico City's main public square.
Andres Manuel Lopez Obrador is seeking a full recount of the vote which saw him lose to conservative Felipe Calderon by half a percentage point.
The Federal Electoral Institute has until 31 August to decide.
The dispute has paralysed Mexican politics, correspondents say.
A president-elect must be declared by 6 September to replace Vicente Fox on 1 December.
'Filthy' poll
This was the third - and the largest - protest by Mr Lopez Obrador's supporters to press their demand for a recount.
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