In the span of one week, Marco Rubio went from a soon-to-be former senator to an incumbent who — by many indications — is preparing for re-election.   

And now, the political world from Washington to Florida waits as the first-term lawmaker decides whether and when to formally declare he’ll seek another term in office — a move that will have important consequences in this year’s battle for the Senate majority.   

There’s still a chance, many Senate GOP operatives caution, that Rubio will decide against re-election. Marc Caputo, a Politico reporter and veteran Rubio scribe, wrote Monday that sources close to the senator say he still hasn’t decided whether to run. 

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Roll Call’s 2016 Election Guide


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But most signals indicate he’s at least on the precipice of jumping back into the race: The New York Times reported late last week that most GOP insiders believe he’ll run . NBC News reported over the weekend that Rubio insiders were instructed to lay the groundwork for a Senate run.   

Asked if he expected Rubio to run, one top Republican strategist replied to Roll Call, “Buckle up.”   

Rubio’s entrance into the campaign would be a major coup for the Senate GOP: The incumbent brings a national fundraising network and near-universal name recognition to an expensive state the size of a small country.    

In their attempts to recruit Rubio, Republican operatives complained openly that the five candidate who had been seeking the GOP nomination lacked the ability to raise enough money to win the battleground seat. Each of them would even lose if Democrats nominated liberal firebrand Rep. Alan Grayson , said Josh Holmes, a former chief of staff to Senate Majority Leader Mitch McConnell.   

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Down but not out: Grayson Plots Longshot Comeback

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One of Rubio’s would-be opponents, Rep. David Jolly, pre-emptively left the Senate race Friday, opting instead to run for re-election in the House.   

But the incumbent’s return to the race doesn’t guarantee the GOP a victory — not with Donald Trump atop the ticket, and not with lingering damage done to Rubio’s image from his failed presidential campaign.   

It was only in March that Rubio lost — badly — in his home state’s GOP presidential primary. And the deep unpopularity of the man who defeated him then, Trump, could alienate huge swaths of voters Rubio needs to win, especially among Latino voters.   

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Rubio for Senate: Will He? Won’t He?

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Democrats are acting as if they expect a Rubio return, too. On Friday, the Democratic Senatorial Campaign Committee released a web video that focused on Rubio’s missed votes in the Senate and some of the unpopular positions he took while in office.   

The favorite to win the Democratic nomination, Rep. Patrick Murphy, on Saturday even blasted his potential opponent as “one of the most homophobic senators in this country.”   

The open Florida seat was rated a Tossup by The Rothenberg & Gonzales Political Report/Roll Call before Rubio’s decision and that wouldn’t change immediately after he announces, even though Republican strategists believe the senator represents the party’s best chance of retaining the Sunshine State seat. If he decides to run, Rubio would join colleagues in New Hampshire, Ohio, Pennsylvania, and Wisconsin who are also running for re-election in competitive states.    

Contact Roarty at alexroarty@cqrollcall.com and follow him on Twitter @Alex_Roarty.