Plaid Cymru should call itself the New Wales Party in a bid to attract voters, leadership hopeful Adam Price has said.
The Carmarthen East and Dinefwr AM said the party needed to create a "story of optimism and hope" to aim for assembly election victories in 2021 and 2026.
Writing for the Western Mail, Mr Price said the proposed name would signal that Plaid "is the party of Wales' future".
Rhun ap Iorwerth is also challenging Plaid leader Leanne Wood for her job.
Mr Price said the party's former leader Dafydd Wigley coined the phrase "New Wales Party" ahead of the first-ever assembly elections in 1999.
He also referred to a party review after the 2011 election, which saw the end of Plaid's spell in government as part of a coalition with Labour.
"That looked at creating a new name in English to signal that we are a pan-Wales party," Mr Price said.
"But what about a new bilingual name to signal that we are the party of Wales' future?"
The article proposed no Welsh version of the suggested new name.
Appearing to criticise Labour's left-wing turn under Jeremy Corbyn, he said: "It sometimes feels as if it's 1983 and the Internet never happened.
"If we want our people to choose a New Wales then perhaps it's time, quite literally, to put it on the ballot."
Mr Price said Plaid Cymru needed to learn from "popular outsider movements" ranging from Labour under Jeremy Corbyn to Donald Trump's election as US President to capture the imagination of people outside the party's core support of "Welsh-identifying, left-of-centre voters".
"We need to create a radical Welsh populism which turns the old Welsh story - a country mistreated, a people let down - into a new Welsh story of optimism and hope," he said.
Plaid Cymru says it expects to announce the winner of the leadership contest on 29 September, a week before the party's autumn conference.