By Alexandra Hudson
NUREMBERG, Germany (Reuters) - Angela Merkel's Free Democrat (FDP) coalition allies finally got into their stride at a weekend congress, mauling the opposition instead of each other and holding up Germans' prosperity compared to European peers as a reason to keep them in power.
With a federal election just under five months away, Merkel's conservatives are strongest in the polls, yet she needs the Free Democrats to build on their recent recovery from three years of dismal ratings if she is to see off the opposition, who are neck and neck with her center-right bloc.
Without the FDP, Merkel would have to chose an alternative coalition partner to secure a third term in office.
The weekend congress, in which the business-friendly party set out its election manifesto of simplified taxes, rigid fiscal discipline, and sector-specific minimum wages, will have given Merkel heart.
The FDP, whose ugly infighting and amateurish gait saw voters desert them in droves in recent years, put on a spirited show at the conference under the banner, "So Germany stays strong".
A thumping theme tune kicked off the event, with the refrain: "I'm doing better ... getting tougher".
"This is the best government for Germany, and will be again for the next four years," said Rainer Bruederle, the party's lead election candidate, to cheers and applause.
"We have always made the Christian Democrats better," he continued, reeling off FDP achievements such as abolishing the draft, reducing household costs, preventing euro bonds and rescue packages for private firms with state funds.
A confident young chairman Philipp Roesler, who in the past has appeared hounded and tense, ridiculed the opposition Greens, as an outdated, musty bunch who obstruct all progress.
He portrayed the Social Democrats as spendthrifts who would raise taxes and borrowing and threaten to drag Germany into the kind of difficulties experienced by euro zone peers.
"Our composure over the last months and the style we've shown, these have won us back the trust of voters," Roesler told an applauding crowd.
The FDP still needs its new-found vigor to translate into a surge in ratings, after a slump from 14.9 percent in 2009.
A new poll by Emnid out on Sunday put the FDP at 5 percent, meeting the threshold needed to win seats in parliament. It also showed the center-right and opposition center-left both neck-and-neck on 42 percent, as Merkel's conservatives shed points after a tax scandal.
Party leaders averted a rebellion to push through a new pledge for minimum wages for non-unionized workers specific to sectors and regions, in a position similar to Merkel's.
Around 5 million workers in Germany - some 16 percent of all employees - earn less than 8.50 euros an hour, which is the minimum wage the center-left opposition wants to see.
The FDP opposes a blanket minimum wage, but Roesler argued that as a matter of social conscience the party should protect workers from pay as low as 3 euros an hour, without endangering jobs and alienating traditional support from business.
"We're on the right path now, with the right messages," said FDP federal lawmaker Jimmy Schulz.
"There is a lot of whinging in Germany, but I'm sure people will realize how good we've got in Germany compared to other European countries and will stick with the center-right."
Andreas Becker, a regional party chairman in Giessen, said he was disappointed by the new minimum wage decision but didn't think it would cause new splits. He dismissed the poor poll ratings, saying the party always bettered them in actual votes.
Pollsters say the FDP - dubbed the party of tax advisers and dentists - has an image problem which often means voters are reluctant to declare their support but prove loyal in the end.
"I'm very optimistic indeed about what I've seen. We hit the right message. We have a healthy economy, very low unemployment and are really living on an island of prosperity here," said one 33-year-old delegate.
"Voters are shy creatures, but they will appear in the end."
(Additional reporting by Thorsten Severin; Editing by Andrew Heavens)