MONTEVIDEO (Reuters) - Uruguay's ruling party on Monday faced a tense five weeks in which to pull together a coalition and fend off a conservative alliance after the leftist candidate Tabare Vazquez fell short of an outright win in the presidential election.
Vazquez, 74, acknowledged on Sunday evening as results trickled in that the Broad Front's fight for a third consecutive presidency would be forced to a runoff on Nov. 30.
On Monday morning, Vazquez maintained a strong lead with 46.5 percent of votes with ballots counted in 90 percent of polling stations, results on the electoral court's website showed. Center-right contender Luis Lacalle Pou had 31.1 percent.
Lacalle Pou's prospects in a runoff were boosted after he secured the swift endorsement of the third placed conservative Colorado Party candidate, Pedro Bordaberry.
Even so, with Bordaberry on course to win about 13 percent of the first round vote, the 41-year-old Lacalle Pou could need the backing of other smaller parties to wrest the presidency from the left.
"From tomorrow (Monday) we will face a new election period in our quest for the presidency of the Republic," Vazquez told supporters late on Sunday night.
The Broad Front has delivered more than a decade of strong economic growth, first under Vazquez who brought it to power for the first time in 2005 and then under his successor and close ally Jose Mujica. Uruguay's constitution does not allow a president two consecutive terms in office.
But many voters have become disenchanted with tax hikes to pay for social welfare measures as well as Mujica's law legalizing the production and sale of marijuana which drew global attention.
Lacalle Pou told Reuters last week he would reverse much of the weed law as well as a decision taken by Mujica to grant six Guantanamo Bay prisoners asylum in the South American country if he won the election.
(Reporting by Malena Castaldi and Esteban Farat; Writing by Richard Lough Editing by W Simon)