Such was public resentment at the perceived impunity of those with connections that two relatively new parties - the far-left Podemos and the centre-right Ciudadanos - rose with meteoric speed on pledges to fight corruption.
But a series of recent prison sentences, arrests and resignations have some cautiously optimistic.
"I wouldn't say that impunity has stopped, but you get the feeling that they're having a bad time and that the cost of corruption is increasing," says Sergio Salgado, spokesman for the XNET corruption whistleblower group.
'As you sow...'
On Tuesday, the son of Catalonia's once hugely influential former regional president Jordi Pujol, who has been under investigation for alleged money laundering for three years, was suddenly jailed on suspicion he hid €30 million ($32.6 million) abroad while the probe was ongoing.
A day earlier, Esperanza Aguirre, an ex-president of the Madrid region and historic figure of the ruling conservative Popular Party (PP), resigned from all her public positions after her former right-hand man Ignacio Gonzalez was jailed pending a probe into embezzlement of public money.
Earlier this month, the president of the southeastern region of Murcia was forced to resign as he too was being probed for alleged corruption.
And while not accused of anything, even Prime Minister Mariano Rajoy has been called to testify as a witness in a major graft trial involving former members of his PP.
"There is sometimes a feeling of impunity, but that's not the case," says Ignacio Gonzalez Vega, spokesman for the Judges for Democracy professional association.
Fernando Vallespin, politics professor at the Autonomous University of Madrid, adds the judicial process may be slow but "ends up being effective."
Or as Rajoy himself told journalists on an official trip to Uruguay: "As you sow, so shall you reap, as is happening," refusing to comment much more on individual cases, many of which involve PP members.
Corruption 'every day'
Still, Jesus Lizcano, head of Transparency International Spain, says there is still "a sensation of alarm."
In the group's last annual corruption perceptions index last year, Spain scored its worst ever ranking.
"Every day we wake up to corruption scandals and there is weariness and outrage," he says.
But for him, this doesn't mean that there is more corruption, "but rather that judges and the police are doing their job well."
He adds that the impunity that may have marked Spain's lavish pre-economic crisis years "no longer exists."
For Salgado, this old feeling of impunity has made those allegedly engaged in corrupt practices "so sloppy and they've left so much evidence that it's turned into their great weak spot."
His XNET group brought to light a major scandal involving Rodrigo Rato, Spain's former superstar economy minister and ex-chief of the International Monetary Fund, who along with others was accused of misusing funds when he ran two Spanish banks.
Salgado recalls that during XNET's investigation into the case, they found many documents signed by the banks' executives that proved their wrongdoing.
"We thought, 'it's impossible that they've left this evidence'."
But it wasn't. And in February, Rato was handed a jail sentence of four years and six months and others were also found guilty.
Around the same time, King Felipe VI's brother-in-law Iñaki Urdangarin (pictured above) was sentenced to over six years in jail for syphoning off millions in a case that shamed the royals.
For the moment, both Rato and Urdangarin have been set free pending their appeals.
But for Salgado, this is still having an effect on others who may be tempted to follow suit.
"When you see that the prime minister is called to testify or you see that Rato, who was an untouchable god... becomes a bad public persona, you're more careful," he says.
By Daniel Bosque / AFP