"He has reduced the debt of Seongnam to zero and rejected political favors. He seems to be very tough on corruption and he has shown his capability in the eyes of public. I think he will do a good job as President," said Daniel Yoo, head of global strategy at Kiwoom Securities.
Interestingly, another potential participant in the 2017 race has also been dubbed as a Korean Bernie Sanders. Ahn Cheol-soo, who ran in the 2012 election as an independent candidate, has earned comparisons with the Vermont senator for his recommended reforms in the education, welfare and chaebol sector. Ahn, a former software tycoon, co-founded the opposition People's Party early this year but resigned in June for the party's alleged involvement in a kickback scandal.
While Ahn was not implicated, the incident has weighed on his popularity; he ranked fourth place in the Gallup Korea poll, with just 8 percent support.
Between Ahn and Lee however, strategists say the latter has a better shot at victory. But it's not clear if Lee can take on fellow Minjoo member Moon Jae-in, a progressive candidate who lost to Park in the 2012 race.
"The anti-establishment sentiment may be strong enough to sweep Lee into office, but he has major headwinds to overcome first," Hastings warned, noting that Lee would need to beat Moon Jae-in in the Minjoo primary before becoming a candidate.
Traditionally, leftist support in South Korea tends to be concentrated in the southwest so Lee will need to attract support from elsewhere in the country, he added.
One thing is certain however, Park's scandal has massively increased the chances of a president from one of the opposition parties. While Saenuri is widely expected to undergo severe rebranding and restructuring to distance itself from Park, that may not be enough to convince the public.
"There's no popular leader on the right... I would be shocked if the left didn't walk away [from the election] victorious. This will be similar to the U.S. Democrats winning after Watergate," Robert Kelly, associate professor at Pusan National University, told CNBC's "Capital Connection" on Monday.
"I would be surprised if Ban Ki-moon can overcome the disdain for Saenuri."
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