German Chancellor Angela Merkel faced down jeering protesters Friday as she embarked on a final push for votes ahead of Sunday's election, seeking to beat back a challenge from the emboldened hard-right. Rowdy dissenters blowing whistles and vuvuzelas and shouting "Get lost" sought to drown out her rally in the southern city of Munich. But the 63-year-old chancellor would not be derailed from her stability-and-prosperity stump speech, telling the crowd that "the future of Germany will definitely not be built up through whistles and hollers." Even though Merkel is expected to secure a fourth term with a double-digit margin of victory, she has been repeatedly confronted by organised protesters at her rallies. Many turn up bearing posters of the anti-immigration Alternative for Germany (AfD), with some even trying to hit Europe's most powerful woman with tomatoes. In a swipe at the AfD, Merkel had told Germans to "go vote and vote for the parties that are 100 percent loyal to our constitution." "We have to take a clear stance when it's about our basic values."    - 'Shame for our nation' -   Mainstream parties are increasingly alarmed by the level of support for the AfD, which looks set to easily clear the five-percent hurdle to representation in parliament in what would be a post-war first. The prospect of an estimated 60 MPs from a nativist outfit branded "real Nazis" by Foreign Minister Sigmar Gabriel taking seats in the Bundestag, the lower house of parliament, has added urgency and angst to what had long been dismissed as a suspense-free campaign. At a rally in central Berlin, Martin Schulz, 61, a former European Parliament president and leader of the centre-left Social Democrats (SPD), vowed that his party would act as a bulwark against the AfD, which he described as an "organisation of rabble-rousers". Briefly giving the floor to a Holocaust survivor, Inge Deutschkron, Schulz said that: "This Alternative for Germany is no alternative. They are a shame for our nation." The AfD is currently polling at around 11 percent, and a strong showing could eat away at Merkel's lead. Her CDU and its Bavarian sister party the CSU were polling at 36 percent according to a new survey late Thursday, close to their worst-ever score of 35.1 percent in 1998. Schulz this week took some succour from Merkel's slipping poll numbers, hoping for a "last-minute turnaround" linked to "growing unease" in the population. But his SPD looks set to fare even worse, garnering an estimated 22 percent, which would be an unmitigated disaster for Germany's oldest party. With the economy humming, business confidence robust and unemployment at post-reunification lows, analysts say there is little appetite for change at the top.   - 'Arrogance of power' -   In trying to appeal to voters disillusioned by Merkel's 12-year tenure, the AfD has railed against her 2015 decision to let more than one million asylum seekers, mainly from Muslim countries, into Germany. Even the mainstream media point to a degree of Merkel fatigue, arguing that the soporific campaign and a sense of complacency could ultimately drive many German voters into the arms of extremists. "For months, Merkel was the phlegmatic queen of the campaign but now, near the finish line, it's not Martin Schulz that is posing a danger but her own ponderousness," Rene Pfister of Der Spiegel wrote. "That antagonises AfD supporters, who in the CDU's confidence of victory see further evidence of the arrogance of power in the late Merkel years."   - 'Political bankruptcy' -   Merkel's chief of staff Peter Altmaier caused a stir this week by suggesting it would be better for Germans not to vote at all than to cast their ballot for the AfD. One of the party's two main candidates, Alice Weidel, denounced the comments as anti-democratic. "Altmaier's declaration is tantamount to admitting political bankruptcy and reveals his disturbed relationship to democracy," she said. AfD supporter Guenther Poppe, a 69-year-old pensioner attending a campaign event in the eastern Berlin district of Marzahn late Thursday, said he refused to be stigmatised for his vote. "The right in Germany has a negative connotation but the AfD could serve as constructive opposition for the good of the German people," he told AFP. But Gerd Appenzeller of Berlin's daily Tagesspiegel warned that any success for the AfD on Sunday night would hit like a bombshell.  "Although the AfD is highly unlikely to fare as well as the extreme right in France or the Netherlands, any relative success for the AfD will reflect badly to international onlookers, given German history," he said. "No amount of rage against Merkel, fury at the SPD, or resignation at modern politics can justify voting for a party that would -- given the chance -- shake this country's foundations to the core."