Palestinians, and some Israelis, see Marwan Barghouti as key to peace. They need him out of prison first

The graffitied image of Marwan Barghouti's face on the huge concrete slabs of Israel's separation barrier, or wall, at the main Israeli checkpoint between Jerusalem and the West Bank city of Ramallah has darkened with the smoke and tear gas of countless demonstrations against an occupation now in its 57th year.  

But his name hasn't faded.

After more than two decades in an Israeli jail, Barghouti remains the most popular Palestinian leader there is, consistently leading opinion polls ahead of Hamas political leader Ismail Haniyeh and Palestinian President Mahmoud Abbas.

For Palestinians, he is a political prisoner. For Israelis, he is a terrorist accused of leading a militant offshoot of the Fatah movement known as the al-Aqsa Martyrs Brigades and convicted of ordering killings and suicide bombings during the second intifada, or uprising.  

With the decimation of Gaza in an Israeli bombing campaign now in its sixth month, and uncertainty over "the day after," calls are growing for Barghouti's release from those who believe he could have an important role to play.

"I'm very confident and very positive that my father will be released," said Barghouti's son Aarab in an interview with CBC News at the offices of the "Free Barghouti" campaign in Ramallah.

"And I can feel that it will happen as soon as possible." 

Last November, 240 Palestinians were released from Israeli jails in exchange for 105 hostages taken by Hamas militants during their attack on Israeli border towns on Oct. 7. 

Around 1,200 people were killed during the Hamas-led attack, according to Israeli tallies. More than 31,000 Palestinians have been killed in Gaza since war broke out, according to Gaza health officials.

Israel and Hamas are trying to negotiate a second exchange. Even though Barghouti has long been a member of the rival Fatah faction that leads the Palestinian Authority, Hamas has put Barghouti's name on its list, as it did last fall.   

Aarab says it's a testament to his father's unifying appeal among Palestinians, and why Israel would be wise to release him.  

"If any Israeli leader really wants an end for this and peace for the region on the long term, they would see that my father is someone that would bring that, who still believes in the tiny chance left for the two-state solution."   

That would be a hard ask for Israelis who see Barghouti as a terrorist with blood on his hands. He was convicted by an Israeli court for his role in the second intifada violence and sentenced to five life terms in 2004. 

Barghouti refused to present a defence to a court whose authority he doesn't recognize but has denied the allegations.