As a divided Republican Party stumbles toward what could become an open presidential nominating convention, a familiar name is resurfacing as a potential contender: Marco Rubio.

  • Online petition asks delegates to unite behind Rubio
  • Petition already has 2,500 signatures
  • Polls show Donald Trump, Ted Cruz still faring poorly among moderate Republicans

Barely a month after the Florida senator ended his bid for the White House, an online petition has been launched to persuade delegates to unite behind him.

The petition, posted on NominateMarco.com, has already garnered 2,500 signatures. In it, its supporters "hereby request that any and all unbound delegates elect Marco Rubio as our nominee" at the Republican National Convention in Cleveland this July.

The petition assumes the party's presidential frontrunner, Donald Trump, won't be able to amass the 1,237 delegates needed to clinch the nomination, in which case other candidates could compete for the prize on the convention floor.

Calling Rubio "the best and most qualified candidate to defeat the Democratic nominee" in the fall, the petition echoes a position trumpeted by the senator's supporters: that his Hispanic heritage, relative youth and policy acumen make him uniquely qualified to win a general election. Polls have shown Trump and Sen. Ted Cruz, the candidate with the second-most delegates, faring poorly among moderate Republicans, independents and crossover Democrats.

The delegates in Cleveland are likely to be dominated by Trump and Cruz devotees, who would be hard-pressed to support an establishment candidate like Rubio.

"It's not as though you're going to have a bunch of sane Republicans going there to vote for Donald Trump or Ted Cruz," said Democratic strategist Steve Schale. "These are Republicans that want Donald Trump or Ted Cruz to be the nominee, who've already rejected a Jeb Bush, have rejected a Marco Rubio. It's going to be exceptionally hard for mainstream Republicans to convince those kind of Republicans to vote for somebody like Rubio."