FACTBOX: Scenarios in autonomy referendum in Bolivia

(Reuters) - Voters in the wealthy Bolivian farming region of Santa Cruz held a referendum on Sunday on a proposal for greater autonomy from the leftist central government.

The pro-autonomy movement is expected to win, in part because of planned vote boycott by Santa Cruz residents who support President Evo Morales and are against the referendum.

The hours and days following the referendum will be key in determining whether the crisis between the central government and the opposition in the provinces will intensify or ease.

Here are some possible scenarios:

YES VOTE, NEGOTIATIONS

Santa Cruz overwhelmingly votes "yes" on autonomy, forcing Morales to negotiate with Bolivia's nine departments on allowing them more control over courts, tax revenue, natural gas production, land reform and even police forces.

Any deals would necessarily have to include agreements on reforms to Bolivia's Constitution, as it does not currently include statutes on autonomy.

Santa Cruz residents might take over central government buildings to celebrate the success of the vote, raising concerns of clashes with opponents.

Three other provinces where the conservative opposition is strong -- Tarija, Beni and Pando -- would likely continue with their plans to hold autonomy referendums but might agree to drop the more extreme demands like having an independent judiciary or immunity from prosecution for local officials, in exchange for having control of their natural resources.

YES VOTE, MORALES REFUSES TO RECOGNIZE IT

If the people of Santa Cruz vote overwhelmingly for autonomy and Morales refuses to recognize the referendum, which he has called illegal, it might spark widespread protests.

In a worst-case scenario, protesters could seize government buildings and the other departments that plan to hold their own autonomy referendums could join the protests, meaning that four of nine provinces turn further against the government.

Morales supporters, mostly the indigenous poor, might respond to protests in defense of the president, and opposition regions could declare independence instead of autonomy, setting the stage for a deeper political crisis in the Andean country.

YES VOTE WITH HIGH ABSTENTION

Santa Cruz residents turn out in low numbers and the "yes" vote is either defeated or wins but with a high abstention rate. This would allow the government to dismiss the autonomy demands as illegitimate and the movement could lose power.

(Reporting by Pav Jordan; Editing by Bill trott)