"That's driven by where Obama is. The president's approval is defining the landscape."
In good news for the president, he still remains personally popular, with a full half of Americans saying they have a positive impression of him.
The president is also seeing growth in key indicators that could bode well for his reelection chances. Of those surveyed, 46 percent approve of his handling of the economy, his best showing in two years. Meanwhile, half of Americans approve of his handling of foreign policy — his best score since 2009 — and 43 percent say the country is headed in the right direction. More than half — 53 percent — are still troubled by the direction of the economy, but those numbers are vastly improved over recent times, and represent the president's best showing in two years.
The poll also showed that Sen. Marco RubioMarco RubioA guide to the committees: Senate Schumer: GOP will break from Trump within months GOP loses top Senate contenders MORE (R-Fla.) would still need to do work to introduce himself to American voters if added to the GOP ticket. A Romney-Rubio pairing trailed a ticket with Romney and former Florida Gov. Jeb Bush, especially among voters in the Midwest.
But that's likely because the popular senator is still an unknown quantity in much of the country.
"Rubio is still fairly unknown," Miringoff said. "I wouldn't say he doesn't bring anything to the ticket. Because of his lack of name ID, it's too early to say."