Bernie Sanders phenomenon has created quite a stir in the placid waters of the two-party US political system. Although Bernie is not running from a third party platform, his camping wears the look of a rank outsider, gatecrashing into the fortress of the US Democratic Party establishment.

In the past, there have been examples of third party candidates making a run at the presidency with a view to cracking open the tightly sealed political terrain between the two main political parties.

The most notable third party candidate was Ralph Nader, the well-known consumer advocate, who made a couple of unsuccessful stabs at the presidency. Yet he felt quite blocked and oppressed by the system. That is why he has endorsed the approach of Bernie Sanders in shaking up the political consensus from within the US Democratic Party system. And Bernie seems to be succeeding to a large extent if judged from reactions coming forth from the Hilary Clinton camp, the Democratic Party establishment candidate.

As an independent senator from Vermont, Sanders commands an impressive record of espousing radical causes over the years. This biography has earned him grudging respect from across the political aisle. By throwing his wild hat into the Democratic Party’s presidential race, he has changed focus from non-issues to real issues and from phony debates around these issues to genuine and engaged debate.

Admittedly, Howard Dean, a radical socialist within the Democratic Party, made such an attempt from within the Democratic Party a couple of presidential elections ago. Yet Dean challenge floundered in early stage because of lack of funds and opposition of the Democratic Party establishment. In fact, Bernie Sanders has picked up where Howard Dean left off. Bernie Sander’s key advisors are drawn from the veterans of Howard Dean’s failed presidential run. In this way, Sanders builds on Dean’s earlier run on an explicitly socialist programmer within the Democratic Party. Part of Sanders’ popularity owes to the momentum generated by the Occupy Movement and other social movements over the years.

Yet what is it that explains Sanders’ staying power and success? And what are the wider implications of Sanders’ phenomenon for the US politics and beyond?

First, Sanders’ success owes a lot to his legitimacy and consistent espousal of issues shut out by the mainstream political parties and the media. Bernie has long been a permanent presence in the US politics, known for advocating consistently radical policy positions on minimum wage, universal healthcare, inequality and widening gap between the rich and poor, education finance reform, US imperial foreign policy, corporate corruption and corporate sponsorship of political candidates. This is rich seam of hot-button issue, which no one has espoused with eloquence and passion as Bernie Sanders has done.

Sanders’ image of a politician with conviction, taking an ideological stand, has endeared him to the wider public long taken for a ride by mainstream politicians of both parties.

Second, his bold advocacy of long-buried, yet politically explosive issues has upset the cozy consensus within the Democratic Party which has got away in the past by merely paying lip service to these issues so fundamental to its base.

Sanders’ message is consistent, direct, unvarnished and radical which has found resonance within the party and the wider electorate. He has gone to the extent of riling up the largest Jewish lobby group by not attending its most important event. This a new and refreshing approach to politics which consist in telling things as they are and how they affect ordinary Americans.

As a result, he has picked up support among young and old alike as the final countdown to the July convention begins. This is quite an astonishing achievement for an independent seeking nomination out of the tight grasp of the established party political elite purely on the strength of radical politics and genuine popular mobilisation.

Third, money is the mother and midwife of the US election, or elections anywhere in the world. Most US politicians sustain their presidential runs with corporate money. Bernie Sanders, in contrast, has inveighed against the influence of corporate money in politics.

Sanders’ campaign has restored the importance of common man in politics by getting money in small contributions from ordinary Americans. This has not only puffed up his electoral war chest, but has also engaged an increasing number of ordinary Americans into his campaign. By doing this he has shown a new way of doing politics and financing presidential runs. This public financing of his presidential run has kept him in the race much to the disappointment of his rivals who had expected him to drop because of lack of money. In fact, he feels so confident of his campaign’s financial health and the wider support that he has pledged to carry his fight right to the July convention. If he manages this, the possibility of upset cannot be discounted.

Despite Sanders’ campaign making a strong comeback by winning last eight out of nine primaries, the mathematics of delegates’ votes is weighted against him. However, there is common agreement that Sanders has already transformed political debate in the US.

First, he has changed the terms of debate within the US Democratic Party. Sanders’ bold and clear-sighted advocacy of issues of inequality, finance, healthcare, corporate corruption, corporate finance, education finance has put out these long-suppressed and simmering hot-button issue in the public domain. This has forced Hillary Clinton into seriously committing herself to define clear-cut positions on issues such as the Wall Street excesses, unfair trade deals and the US military interventions.

This lively and no-holds barred political conversation has triggered interest of the youth in the US politics.

Second, for the first time in US politics, socialism is no more a dirty word. Sanders openly identifies himself as a democratic socialist. His message has resonated with the wider electorate and the US Democratic Party’s base. Influential magazines such as the Atlantic are already carrying articles about the US population’s increasingly left-leaning drift. And Sanders’ contribution to this sea-change in political attitude is immense.

Sanders has clearly shown what a public-funded presidential candidate looks like as opposed to a clutch of corporate-funded presidential candidates. This may, at the end of the day, be his lasting legacy to a system known for throwing up corporate-funded candidates with little policy differences between them.