The official line is that Marco Rubio is talking things over with his family this weekend, with a final decision due soon.
But CNN's Chief National Correspondent John King is reporting that barring some unexpected last-minute glitch, Rubio is set to jump back into the Senate race in the week ahead, according to several Republicans involved in the deliberations.
"The Florida senator is telling top supporters he has changed his mind -- and will run for re-election to the Senate," said King. "This change of heart will be a boost to Republican hopes of holding their Senate majority after a tough couple of weeks."
Strategists working key Senate races in Ohio, Wisconsin, Pennsylvania and New Hampshire report a drop in Donald Trump's numbers in those states, and there are growing worries he could drag some Senate incumbents down with him if he is unable to reverse his fortunes.
Florida was another big worry -- because Rubio was adamant after his presidential campaign fizzled that he was leaving Washington. Now, with Rubio reversing course, Republicans are a lot more optimistic about the Sunshine State.
2. Trump's UK reset --"to go or not to go" to Scotland?
Donald Trump is heading to Scotland next week -- right after the UK votes on whether or not it should stay in the European Union.
And The New York Times' Maggie Haberman reveals it's a trip that some of his advisers are hoping he will cancel.
"It's coming right after the Brexit vote -- it's a very tumultuous time across the pond -- there was just a slain politician," said Haberman. "He's also not planning on making any kind of high-level meetings there. He's going to literally go from one golf property to another."
"So there are some people who, while that might help him reset and be in a comfort area, are hopeful that he will ultimately decide this is not where he should be."
3. The billionaire's bottom line
Trump has been generating a lot of headlines this weekend by saying he didn't need the GOP to help him fund his campaign -- but if they didn't help him, he wouldn't help them.
"Life is like a two-way street," said Trump in Las Vegas Saturday. "They have to [help], otherwise I'll keep doing what I am doing. I'll just keep funding my own campaign. I'm ok with that. That's the easy way."
How much money is he actually contributing to his own campaign?
CNN's MJ Lee points out that Monday is the FEC filing deadline for May and those numbers will reveal where the billionaire's backers are coming from and how his general election fund-raising figures stack up to Clinton's.
"Two things I think are worth watching: the first is whether Trump has given himself more money," said Lee. "The second thing is how he sort of sets expectations in terms of how much money he thinks he'll be able to raise and also how much money he thinks he needs to raise."
4. Clinton's "Define Donald" playbook -- the next step
Next up in Hillary Clinton's ongoing Trump lecture series: the economy.
In Columbus on Tuesday, Clinton picks up where she left off in her widely-covered foreign policy speech in San Diego, where she declared Trump unfit for the presidency.
CNN's Jeff Zeleny reports she will unleash a detailed take-down of Trump's business record, arguing that he's only looking out for himself, at the cost of American workers and a middle-class that's invisible to him.
"It's part of the Clinton campaign's continued effort to define Donald Trump early," said Zeleny. "It's one thing after another on this but it raises the question: can she get to the White House -- can she win in November on anti-Trump sentiment alone? The campaign believes no."
That's why Zeleny also points out the campaign is making a big investment in battleground state ads on her biography.
Which tactic will shape the race more? Only time will tell.
5. Clinton's Ohio veepstakes pick?
As the running-mate guessing game ramps up in both parties, The New York Times' Jonathan Martin zeroes in on a name that popped up last week in a Wall Street Journal write up -- a young congressman with working class credentials, Tim Ryan of Ohio.
"As these things work, there are often names that are put in circulation by campaigns who like surrogates," said Martin. "I think Ryan falls in that category."
"He's probably not going to be the pick, but keep an eye on him for either a slot in the administration or to run for governor of Ohio in 2018. The Clinton folks like him a lot."